Merge pull request #1366 from hapifhir/2023-07-gg-fhirpath-fixes

2023 07 gg fhirpath fixes

org.hl7.fhir.r4b/src/main/java/org/hl7/fhir/r4b/utils/FHIRLexer.java

@@ -48,24 +48,34 @@ import org.hl7.fhir.utilities.Utilities;
 public class FHIRLexer {
   public class FHIRLexerException extends FHIRException {
 
-    public FHIRLexerException() {
+    private SourceLocation location;
-      super();
-    }
 
-    public FHIRLexerException(String message, Throwable cause) {
+//    public FHIRLexerException() {
-      super(message, cause);
+//      super();
-    }
+//    }
+//
+//    public FHIRLexerException(String message, Throwable cause) {
+//      super(message, cause);
+//    }
+//
+//    public FHIRLexerException(String message) {
+//      super(message);
+//    }
+//
+//    public FHIRLexerException(Throwable cause) {
+//      super(cause);
+//    }
 
-    public FHIRLexerException(String message) {
+    public FHIRLexerException(String message, SourceLocation location) {
       super(message);
+      this.location = location;
     }
 
-    public FHIRLexerException(Throwable cause) {
+    public SourceLocation getLocation() {
-      super(cause);
+      return location;
     }
 
   }
-
   private String source;
   private int cursor;
   private int currentStart;
@@ -75,8 +85,10 @@ public class FHIRLexer {
   private SourceLocation currentStartLocation;
   private int id;
   private String name;
-  private boolean liquidMode; // in liquid mode, || terminates the expression and hands the parser back to the
+  private boolean liquidMode; // in liquid mode, || terminates the expression and hands the parser back to the host
-                              // host
+  private SourceLocation commentLocation;
+  private boolean metadataFormat;
+  private boolean allowDoubleQuotes;
 
   public FHIRLexer(String source, String name) throws FHIRLexerException {
     this.source = source == null ? "" : source;
@@ -84,35 +96,44 @@ public class FHIRLexer {
     currentLocation = new SourceLocation(1, 1);
     next();
   }
-
   public FHIRLexer(String source, int i) throws FHIRLexerException {
     this.source = source;
     this.cursor = i;
     currentLocation = new SourceLocation(1, 1);
     next();
   }
-
+  public FHIRLexer(String source, int i, boolean allowDoubleQuotes) throws FHIRLexerException {
+    this.source = source;
+    this.cursor = i;
+    this.allowDoubleQuotes =  allowDoubleQuotes;
+    currentLocation = new SourceLocation(1, 1);
+    next();
+  }
+  public FHIRLexer(String source, String name, boolean metadataFormat, boolean allowDoubleQuotes) throws FHIRLexerException {
+    this.source = source == null ? "" : source;
+    this.name = name == null ? "??" : name;
+    this.metadataFormat = metadataFormat;
+    this.allowDoubleQuotes =  allowDoubleQuotes;
+    currentLocation = new SourceLocation(1, 1);
+    next();
+  }
   public String getCurrent() {
     return current;
   }
-
   public SourceLocation getCurrentLocation() {
     return currentLocation;
   }
 
   public boolean isConstant() {
-    return !Utilities.noString(current) && ((current.charAt(0) == '\'' || current.charAt(0) == '"')
+    return FHIRPathConstant.isFHIRPathConstant(current);
-        || current.charAt(0) == '@' || current.charAt(0) == '%' || current.charAt(0) == '-' || current.charAt(0) == '+'
-        || (current.charAt(0) >= '0' && current.charAt(0) <= '9') || current.equals("true") || current.equals("false")
-        || current.equals("{}"));
   }
 
   public boolean isFixedName() {
-    return current != null && (current.charAt(0) == '`');
+    return FHIRPathConstant.isFHIRPathFixedName(current);
   }
 
   public boolean isStringConstant() {
-    return current.charAt(0) == '\'' || current.charAt(0) == '"' || current.charAt(0) == '`';
+    return FHIRPathConstant.isFHIRPathStringConstant(current);
   }
 
   public String take() throws FHIRLexerException {
@@ -139,12 +160,10 @@ public class FHIRLexer {
     if (current.equals("*") || current.equals("**"))
       return true;
 
-    if ((current.charAt(0) >= 'A' && current.charAt(0) <= 'Z')
+    if ((current.charAt(0) >= 'A' && current.charAt(0) <= 'Z') || (current.charAt(0) >= 'a' && current.charAt(0) <= 'z')) {
-        || (current.charAt(0) >= 'a' && current.charAt(0) <= 'z')) {
       for (int i = 1; i < current.length(); i++) 
-        if (!((current.charAt(1) >= 'A' && current.charAt(1) <= 'Z')
+        if (!( (current.charAt(1) >= 'A' && current.charAt(1) <= 'Z') || (current.charAt(1) >= 'a' && current.charAt(1) <= 'z') ||
-            || (current.charAt(1) >= 'a' && current.charAt(1) <= 'z')
+            (current.charAt(1) >= '0' && current.charAt(1) <= '9')))
-            || (current.charAt(1) >= '0' && current.charAt(1) <= '9')))
           return false;
       return true;
     }
@@ -152,11 +171,11 @@ public class FHIRLexer {
   }
 
   public FHIRLexerException error(String msg) {
-    return error(msg, currentLocation.toString());
+    return error(msg, currentLocation.toString(), currentLocation);
   }
 
-  public FHIRLexerException error(String msg, String location) {
+  public FHIRLexerException error(String msg, String location, SourceLocation loc) {
-    return new FHIRLexerException("Error @" + location + ": " + msg);
+    return new FHIRLexerException("Error @"+location+": "+msg, loc);
   }
 
   public void next() throws FHIRLexerException {
@@ -168,9 +187,7 @@ public class FHIRLexer {
       char ch = source.charAt(cursor);
       if (ch == '!' || ch == '>' || ch == '<' || ch == ':' || ch == '-' || ch == '=')  {
         cursor++;
-        if (cursor < source.length()
+        if (cursor < source.length() && (source.charAt(cursor) == '=' || source.charAt(cursor) == '~' || source.charAt(cursor) == '-') || (ch == '-' && source.charAt(cursor) == '>')) 
-            && (source.charAt(cursor) == '=' || source.charAt(cursor) == '~' || source.charAt(cursor) == '-')
-            || (ch == '-' && source.charAt(cursor) == '>'))
           cursor++;
         current = source.substring(currentStart, cursor);
       } else if (ch == '.' ) {
@@ -181,8 +198,7 @@ public class FHIRLexer {
       } else if (ch >= '0' && ch <= '9') {
           cursor++;
         boolean dotted = false;
-        while (cursor < source.length() && ((source.charAt(cursor) >= '0' && source.charAt(cursor) <= '9')
+        while (cursor < source.length() && ((source.charAt(cursor) >= '0' && source.charAt(cursor) <= '9') || (source.charAt(cursor) == '.') && !dotted)) {
-            || (source.charAt(cursor) == '.') && !dotted)) {
           if (source.charAt(cursor) == '.')
             dotted = true;
           cursor++;
@@ -191,9 +207,8 @@ public class FHIRLexer {
           cursor--;
         current = source.substring(currentStart, cursor);
       }  else if ((ch >= 'a' && ch <= 'z') || (ch >= 'A' && ch <= 'Z')) {
-        while (cursor < source.length() && ((source.charAt(cursor) >= 'A' && source.charAt(cursor) <= 'Z')
+        while (cursor < source.length() && ((source.charAt(cursor) >= 'A' && source.charAt(cursor) <= 'Z') || (source.charAt(cursor) >= 'a' && source.charAt(cursor) <= 'z') || 
-            || (source.charAt(cursor) >= 'a' && source.charAt(cursor) <= 'z')
+            (source.charAt(cursor) >= '0' && source.charAt(cursor) <= '9') || source.charAt(cursor) == '_')) 
-            || (source.charAt(cursor) >= '0' && source.charAt(cursor) <= '9') || source.charAt(cursor) == '_'))
           cursor++;
         current = source.substring(currentStart, cursor);
       } else if (ch == '%') {
@@ -204,19 +219,20 @@ public class FHIRLexer {
             cursor++;
           cursor++;
         } else
-          while (cursor < source.length() && ((source.charAt(cursor) >= 'A' && source.charAt(cursor) <= 'Z')
+        while (cursor < source.length() && ((source.charAt(cursor) >= 'A' && source.charAt(cursor) <= 'Z') || (source.charAt(cursor) >= 'a' && source.charAt(cursor) <= 'z') || 
-              || (source.charAt(cursor) >= 'a' && source.charAt(cursor) <= 'z')
+            (source.charAt(cursor) >= '0' && source.charAt(cursor) <= '9') || source.charAt(cursor) == ':' || source.charAt(cursor) == '-'))
-              || (source.charAt(cursor) >= '0' && source.charAt(cursor) <= '9') || source.charAt(cursor) == ':'
-              || source.charAt(cursor) == '-'))
           cursor++;
         current = source.substring(currentStart, cursor);
       } else if (ch == '/') {
         cursor++;
         if (cursor < source.length() && (source.charAt(cursor) == '/')) {
-          // this is en error - should already have been skipped
+          // we've run into metadata
-          error("This shouldn't happen?");
+          cursor++;
-        }
+          cursor++;
           current = source.substring(currentStart, cursor);
+        } else {
+          current = source.substring(currentStart, cursor);
+        }
       } else if (ch == '$') {
         cursor++;
         while (cursor < source.length() && (source.charAt(cursor) >= 'a' && source.charAt(cursor) <= 'z'))
@@ -228,7 +244,7 @@ public class FHIRLexer {
         if (ch == '}')
           cursor++;
         current = source.substring(currentStart, cursor);
-      } else if (ch == '"') {
+      } else if (ch == '"' && allowDoubleQuotes) {
         cursor++;
         boolean escape = false;
         while (cursor < source.length() && (escape || source.charAt(cursor) != '"')) {
@@ -308,16 +324,23 @@ public class FHIRLexer {
 
   private void skipWhitespaceAndComments() {
     comments.clear();
+    commentLocation = null;
     boolean last13 = false;
     boolean done = false;
     while (cursor < source.length() && !done) {
-      if (cursor < source.length() - 1 && "//".equals(source.substring(cursor, cursor + 2))) {
+      if (cursor < source.length() -1 && "//".equals(source.substring(cursor, cursor+2)) && !isMetadataStart()) {
+        if (commentLocation == null) {
+          commentLocation = currentLocation.copy();
+        }
         int start = cursor+2;
         while (cursor < source.length() && !((source.charAt(cursor) == '\r') || source.charAt(cursor) == '\n')) { 
           cursor++;        
         }
         comments.add(source.substring(start, cursor).trim());
       } else if (cursor < source.length() - 1 && "/*".equals(source.substring(cursor, cursor+2))) {
+        if (commentLocation == null) {
+          commentLocation = currentLocation.copy();
+        }
         int start = cursor+2;
         while (cursor < source.length() - 1 && !"*/".equals(source.substring(cursor, cursor+2))) { 
           last13 = currentLocation.checkChar(source.charAt(cursor), last13);
@@ -329,7 +352,7 @@ public class FHIRLexer {
           comments.add(source.substring(start, cursor).trim());
           cursor = cursor + 2;
         }
-      } else if (Character.isWhitespace(source.charAt(cursor))) {
+      } else if (Utilities.isWhitespace(source.charAt(cursor))) {
         last13 = currentLocation.checkChar(source.charAt(cursor), last13);
         cursor++;
       } else {
@@ -338,27 +361,25 @@ public class FHIRLexer {
     }
   }
   
+  private boolean isMetadataStart() {
+    return metadataFormat && cursor < source.length() - 2 && "///".equals(source.substring(cursor, cursor+3));
+  }
+  
   private boolean isDateChar(char ch,int start) {
     int eot = source.charAt(start+1) == 'T' ? 10 : 20;
     
-    return ch == '-' || ch == ':' || ch == 'T' || ch == '+' || ch == 'Z' || Character.isDigit(ch)
+    return ch == '-' || ch == ':' || ch == 'T' || ch == '+' || ch == 'Z' || Character.isDigit(ch) || (cursor-start == eot && ch == '.' && cursor < source.length()-1&& Character.isDigit(source.charAt(cursor+1)));
-        || (cursor - start == eot && ch == '.' && cursor < source.length() - 1
-            && Character.isDigit(source.charAt(cursor + 1)));
   }
-
   public boolean isOp() {
     return ExpressionNode.Operation.fromCode(current) != null;
   }
-
   public boolean done() {
     return currentStart >= source.length();
   }
-
   public int nextId() {
     id++;
     return id;
   }
-
   public SourceLocation getCurrentStartLocation() {
     return currentStartLocation;
   }
@@ -396,7 +417,6 @@ public class FHIRLexer {
   public boolean hasToken(String kw) {
     return !done() && kw.equals(current);
   }
-
   public boolean hasToken(String... names) {
     if (done()) 
       return false;
@@ -468,7 +488,7 @@ public class FHIRLexer {
           i = i + 4;
           break;
         default:
-          throw new FHIRLexerException("Unknown character escape \\" + s.charAt(i));
+          throw new FHIRLexerException("Unknown character escape \\"+s.charAt(i), currentLocation);
         }
       } else {
         b.append(ch);
@@ -517,7 +537,7 @@ public class FHIRLexer {
           i = i + 4;
           break;
         default:
-          throw new FHIRLexerException("Unknown character escape \\" + s.charAt(i));
+          throw new FHIRLexerException("Unknown character escape \\"+s.charAt(i), currentLocation);
         }
       } else {
         b.append(ch);
@@ -532,7 +552,6 @@ public class FHIRLexer {
       next();
     
   }
-
   public String takeDottedToken() throws FHIRLexerException {
     StringBuilder b = new StringBuilder();
     b.append(take());
@@ -546,17 +565,39 @@ public class FHIRLexer {
   public int getCurrentStart() {
     return currentStart;
   }
-
   public String getSource() {
     return source;
   }
-
   public boolean isLiquidMode() {
     return liquidMode;
   }
-
   public void setLiquidMode(boolean liquidMode) {
     this.liquidMode = liquidMode;
   }
-
+  public SourceLocation getCommentLocation() {
+    return this.commentLocation;
+  }
+  public boolean isMetadataFormat() {
+    return metadataFormat;
+  }
+  public void setMetadataFormat(boolean metadataFormat) {
+    this.metadataFormat = metadataFormat;
+  }
+  public List<String> cloneComments() {
+    List<String> res = new ArrayList<>();
+    res.addAll(getComments());
+    return res;
+  }
+  public String tokenWithTrailingComment(String token) {
+    int line = getCurrentLocation().getLine();
+    token(token);
+    if (getComments().size() > 0 && getCommentLocation().getLine() == line) {
+      return getFirstComment();
+    } else {
+      return null;
+    }
+  }
+  public boolean isAllowDoubleQuotes() {
+    return allowDoubleQuotes;
+  }
 }

org.hl7.fhir.r4b/src/main/java/org/hl7/fhir/r4b/utils/FHIRPathConstant.java

@@ -0,0 +1,20 @@
+package org.hl7.fhir.r4b.utils;
+
+import org.hl7.fhir.utilities.Utilities;
+
+public class FHIRPathConstant {
+
+  public static boolean isFHIRPathConstant(String string) {
+    return !Utilities.noString(string) && ((string.charAt(0) == '\'' || string.charAt(0) == '"') || string.charAt(0) == '@' || string.charAt(0) == '%' ||
+      string.charAt(0) == '-' || string.charAt(0) == '+' || (string.charAt(0) >= '0' && string.charAt(0) <= '9') ||
+      string.equals("true") || string.equals("false") || string.equals("{}"));
+  }
+
+  public static boolean isFHIRPathFixedName(String string) {
+    return string != null && (string.charAt(0) == '`');
+  }
+
+  public static boolean isFHIRPathStringConstant(String string) {
+    return string.charAt(0) == '\'' || string.charAt(0) == '"' || string.charAt(0) == '`';
+  }
+}

org.hl7.fhir.r4b/src/main/java/org/hl7/fhir/r4b/utils/FHIRPathEngine.java

@@ -282,6 +282,7 @@ public class FHIRPathEngine {
                               // host
   private boolean doNotEnforceAsSingletonRule;
   private boolean doNotEnforceAsCaseSensitive;
+  private boolean allowDoubleQuotes;
 
   // if the fhir path expressions are allowed to use constants beyond those
   // defined in the specification
@@ -531,7 +532,7 @@ public class FHIRPathEngine {
   }
 
   public ExpressionNode parse(String path, String name) throws FHIRLexerException {
-    FHIRLexer lexer = new FHIRLexer(path, name);
+    FHIRLexer lexer = new FHIRLexer(path, name, false, allowDoubleQuotes);
     if (lexer.done()) {
       throw lexer.error("Path cannot be empty");
     }
@@ -572,7 +573,7 @@ public class FHIRPathEngine {
    * @throws Exception
    */
   public ExpressionNodeWithOffset parsePartial(String path, int i) throws FHIRLexerException {
-    FHIRLexer lexer = new FHIRLexer(path, i);
+    FHIRLexer lexer = new FHIRLexer(path, i, allowDoubleQuotes);
     if (lexer.done()) {
       throw lexer.error("Path cannot be empty");
     }
@@ -1400,8 +1401,7 @@ public class FHIRPathEngine {
   private boolean checkParamCount(FHIRLexer lexer, SourceLocation location, ExpressionNode exp, int count)
       throws FHIRLexerException {
     if (exp.getParameters().size() != count) {
-      throw lexer.error("The function \"" + exp.getName() + "\" requires " + Integer.toString(count) + " parameters",
+      throw lexer.error("The function \"" + exp.getName() + "\" requires " + Integer.toString(count) + " parameters");
-          location.toString());
     }
     return true;
   }
@@ -1410,7 +1410,7 @@ public class FHIRPathEngine {
       int countMax) throws FHIRLexerException {
     if (exp.getParameters().size() < countMin || exp.getParameters().size() > countMax) {
       throw lexer.error("The function \"" + exp.getName() + "\" requires between " + Integer.toString(countMin)
-          + " and " + Integer.toString(countMax) + " parameters", location.toString());
+          + " and " + Integer.toString(countMax) + " parameters");
     }
     return true;
   }
@@ -6722,4 +6722,14 @@ public class FHIRPathEngine {
     this.liquidMode = liquidMode;
   }
 
+  public ProfileUtilities getProfileUtilities() {
+    return profileUtilities;
+  }
+
+  public boolean isAllowDoubleQuotes() {
+    return allowDoubleQuotes;
+  }
+  public void setAllowDoubleQuotes(boolean allowDoubleQuotes) {
+    this.allowDoubleQuotes = allowDoubleQuotes;    
+  }
 }

org.hl7.fhir.r4b/src/main/java/org/hl7/fhir/r4b/utils/LiquidEngine.java

@@ -50,6 +50,7 @@ import org.hl7.fhir.r4b.model.ValueSet;
 import org.hl7.fhir.r4b.utils.FHIRPathEngine.ExpressionNodeWithOffset;
 import org.hl7.fhir.r4b.utils.FHIRPathEngine.IEvaluationContext;
 import org.hl7.fhir.utilities.Utilities;
+import org.hl7.fhir.utilities.i18n.I18nConstants;
 import org.hl7.fhir.utilities.xhtml.NodeType;
 import org.hl7.fhir.utilities.xhtml.XhtmlNode;
 
@@ -70,17 +71,27 @@ public class LiquidEngine implements IEvaluationContext {
 
   private class LiquidEngineContext {
     private Object externalContext;
-    private Map<String, Base> vars = new HashMap<>();
+    private Map<String, Base> loopVars = new HashMap<>();
+    private Map<String, Base> globalVars = new HashMap<>();
 
     public LiquidEngineContext(Object externalContext) {
       super();
       this.externalContext = externalContext;
+      globalVars = new HashMap<>();
+    }
+
+    public LiquidEngineContext(Object externalContext, LiquidEngineContext existing) {
+      super();
+      this.externalContext = externalContext;
+      loopVars.putAll(existing.loopVars);
+      globalVars = existing.globalVars;
     }
 
     public LiquidEngineContext(LiquidEngineContext existing) {
       super();
       externalContext = existing.externalContext;
-      vars.putAll(existing.vars);
+      loopVars.putAll(existing.loopVars);
+      globalVars = existing.globalVars;
     }
   }
 
@@ -121,6 +132,7 @@ public class LiquidEngine implements IEvaluationContext {
     return b.toString();
   }
   
+
   private abstract class LiquidNode {
     protected void closeUp() {
     }
@@ -163,7 +175,6 @@ public class LiquidEngine implements IEvaluationContext {
   private class LiquidExpressionNode {
     private LiquidFilter filter; // null at root
     private ExpressionNode expression; // null for some filters
-
     public LiquidExpressionNode(LiquidFilter filter, ExpressionNode expression) {
       super();
       this.filter = filter;
@@ -179,7 +190,7 @@ public class LiquidEngine implements IEvaluationContext {
     @Override
     public void evaluate(StringBuilder b, Base resource, LiquidEngineContext ctxt) throws FHIRException {
       if (compiled.size() == 0) {
-        FHIRLexer lexer = new FHIRLexer(statement, "liquid statement");
+        FHIRLexer lexer = new FHIRLexer(statement, "liquid statement", false, true);
         lexer.setLiquidMode(true);
         compiled.add(new LiquidExpressionNode(null, engine.parse(lexer)));
         while (!lexer.done()) {
@@ -188,7 +199,7 @@ public class LiquidEngine implements IEvaluationContext {
             String f = lexer.getCurrent();
             LiquidFilter filter = LiquidFilter.fromCode(f);
             if (filter == null) {
-              lexer.error("Unknown Liquid filter '" + f + "'");
+              lexer.error(engine.getWorker().formatMessage(I18nConstants.LIQUID_UNKNOWN_FILTER, f));
             }
             lexer.next();
             if (!lexer.done() && lexer.getCurrent().equals(":")) {
@@ -198,7 +209,7 @@ public class LiquidEngine implements IEvaluationContext {
               compiled.add(new LiquidExpressionNode(filter, null));
             }
           } else {
-            lexer.error("Unexpected syntax parsing liquid statement");
+            lexer.error(engine.getWorker().formatMessage(I18nConstants.LIQUID_UNKNOWN_SYNTAX)); 
           }
         }
       }
@@ -207,8 +218,7 @@ public class LiquidEngine implements IEvaluationContext {
       for (LiquidExpressionNode i : compiled) {
         if (i.filter == null) { // first
           t = stmtToString(ctxt, engine.evaluate(ctxt, resource, resource, resource, i.expression));
-        } else
+        } else switch (i.filter) {
-          switch (i.filter) {
         case PREPEND:
           t = stmtToString(ctxt, engine.evaluate(ctxt, resource, resource, resource, i.expression)) + t;
           break;
@@ -221,10 +231,7 @@ public class LiquidEngine implements IEvaluationContext {
       StringBuilder b = new StringBuilder();
       boolean first = true;
       for (Base i : items) {
-        if (first)
+        if (first) first = false; else b.append(", ");
-          first = false;
-        else
-          b.append(", ");
         String s = renderingSupport != null ? renderingSupport.renderForLiquid(ctxt.externalContext, i) : null;
         b.append(s != null ? s : engine.convertToString(i));
       }
@@ -312,6 +319,30 @@ public class LiquidEngine implements IEvaluationContext {
     }
   }
 
+  private class LiquidAssign extends LiquidNode {
+    private String varName;
+    private String expression;
+    private ExpressionNode compiled;
+    @Override
+    public void evaluate(StringBuilder b, Base resource, LiquidEngineContext ctxt) throws FHIRException {
+      if (compiled == null) {
+        boolean dbl = engine.isAllowDoubleQuotes();
+        engine.setAllowDoubleQuotes(true);
+        ExpressionNodeWithOffset po = engine.parsePartial(expression, 0);
+        compiled = po.getNode();
+        engine.setAllowDoubleQuotes(dbl);
+      }
+      List<Base> list = engine.evaluate(ctxt, resource, resource, resource, compiled);
+      if (list.isEmpty()) {
+        ctxt.globalVars.remove(varName);
+      } else if (list.size() == 1) {
+        ctxt.globalVars.put(varName, list.get(0));
+      } else {
+        throw new Error("Assign returned a list?");
+      }      
+    }    
+  }
+  
   private class LiquidFor extends LiquidNode {
     private String varName;
     private String condition;
@@ -350,7 +381,10 @@ public class LiquidEngine implements IEvaluationContext {
           if (limit >= 0 && i == limit) {
             break;
           }          
-          lctxt.vars.put(varName, o);
+          if (lctxt.globalVars.containsKey(varName)) {
+            throw new FHIRException(engine.getWorker().formatMessage(I18nConstants.LIQUID_VARIABLE_ALREADY_ASSIGNED, varName));
+          }
+          lctxt.loopVars.put(varName, o);
           boolean wantBreak = false;
           for (LiquidNode n : body) {
             try {
@@ -379,7 +413,7 @@ public class LiquidEngine implements IEvaluationContext {
         } else if (cnt.startsWith("limit")) {
           cnt = cnt.substring(5).trim();
           if (!cnt.startsWith(":")) {
-            throw new FHIRException("Exception evaluating " + src + ": limit is not followed by ':'");
+            throw new FHIRException(engine.getWorker().formatMessage(I18nConstants.LIQUID_SYNTAX_COLON, src));
           }
           cnt = cnt.substring(1).trim();
           int i = 0;
@@ -387,14 +421,14 @@ public class LiquidEngine implements IEvaluationContext {
             i++;
           }
           if (i == 0) {
-            throw new FHIRException("Exception evaluating " + src + ": limit is not followed by a number");
+            throw new FHIRException(engine.getWorker().formatMessage(I18nConstants.LIQUID_SYNTAX_NUMBER, src));
           }
           limit = Integer.parseInt(cnt.substring(0, i));
           cnt = cnt.substring(i);
         } else if (cnt.startsWith("offset")) {
           cnt = cnt.substring(6).trim();
           if (!cnt.startsWith(":")) {
-            throw new FHIRException("Exception evaluating " + src + ": limit is not followed by ':'");
+            throw new FHIRException(engine.getWorker().formatMessage(I18nConstants.LIQUID_SYNTAX_COLON, src));
           }
           cnt = cnt.substring(1).trim();
           int i = 0;
@@ -402,12 +436,12 @@ public class LiquidEngine implements IEvaluationContext {
             i++;
           }
           if (i == 0) {
-            throw new FHIRException("Exception evaluating " + src + ": limit is not followed by a number");
+            throw new FHIRException(engine.getWorker().formatMessage(I18nConstants.LIQUID_SYNTAX_NUMBER, src));
           }
           offset = Integer.parseInt(cnt.substring(0, i));
           cnt = cnt.substring(i);
         } else {
-          throw new FHIRException("Exception evaluating " + src + ": unexpected content at " + cnt);
+          throw new FHIRException(engine.getWorker().formatMessage(I18nConstants.LIQUID_SYNTAX_UNEXPECTED, cnt));
         }
       }      
     }
@@ -422,9 +456,9 @@ public class LiquidEngine implements IEvaluationContext {
       String src = includeResolver.fetchInclude(LiquidEngine.this, page);
       LiquidParser parser = new LiquidParser(src);
       LiquidDocument doc = parser.parse(page);
-      LiquidEngineContext nctxt = new LiquidEngineContext(ctxt.externalContext);
+      LiquidEngineContext nctxt = new LiquidEngineContext(ctxt.externalContext, ctxt);
       Tuple incl = new Tuple();
-      nctxt.vars.put("include", incl);
+      nctxt.loopVars.put("include", incl);
       for (String s : params.keySet()) {
         incl.addProperty(s, engine.evaluate(ctxt, resource, resource, resource, params.get(s)));
       }
@@ -481,13 +515,11 @@ public class LiquidEngine implements IEvaluationContext {
       cnt = "," + cnt.substring(5).trim();
       while (!Utilities.noString(cnt)) {
         if (!cnt.startsWith(",")) {
-          throw new FHIRException(
+          throw new FHIRException(engine.getWorker().formatMessage(I18nConstants.LIQUID_SYNTAX_EXPECTING, name, cnt.charAt(0), ','));
-              "Script " + name + ": Script " + name + ": Found " + cnt.charAt(0) + " expecting ',' parsing cycle");
         }
         cnt = cnt.substring(1).trim();
         if (!cnt.startsWith("\"")) {
-          throw new FHIRException(
+          throw new FHIRException(engine.getWorker().formatMessage(I18nConstants.LIQUID_SYNTAX_EXPECTING, name, cnt.charAt(0), '"'));
-              "Script " + name + ": Script " + name + ": Found " + cnt.charAt(0) + " expecting '\"' parsing cycle");
         }
         cnt = cnt.substring(1);
         int i = 0;
@@ -495,7 +527,7 @@ public class LiquidEngine implements IEvaluationContext {
           i++;
         }
         if (i == cnt.length()) {
-          throw new FHIRException("Script " + name + ": Script " + name + ": Found unterminated string parsing cycle");
+          throw new FHIRException(engine.getWorker().formatMessage(I18nConstants.LIQUID_SYNTAX_UNTERMINATED, name));
         }
         res.list.add(cnt.substring(0, i));
         cnt = cnt.substring(i + 1).trim();
@@ -527,9 +559,10 @@ public class LiquidEngine implements IEvaluationContext {
               list.add(parseCycle(cnt));
             else if (cnt.startsWith("include "))
               list.add(parseInclude(cnt.substring(7).trim()));
+            else if (cnt.startsWith("assign "))
+              list.add(parseAssign(cnt.substring(6).trim()));
             else
-              throw new FHIRException(
+              throw new FHIRException(engine.getWorker().formatMessage(I18nConstants.LIQUID_UNKNOWN_FLOW_STMT,name, cnt));
-                  "Script " + name + ": Script " + name + ": Unknown flow control statement " + cnt);
           } else { // next2() == '{'
             list.add(parseStatement());
           }
@@ -543,8 +576,7 @@ public class LiquidEngine implements IEvaluationContext {
         n.closeUp();
       if (terminators.length > 0)
         if (!isTerminator(close, terminators))
-          throw new FHIRException(
+          throw new FHIRException(engine.getWorker().formatMessage(I18nConstants.LIQUID_UNKNOWN_NOEND, name, terminators));
-              "Script " + name + ": Script " + name + ": Found end of script looking for " + terminators);
       return close;
     }
 
@@ -588,7 +620,7 @@ public class LiquidEngine implements IEvaluationContext {
       while (i < cnt.length() && !Character.isWhitespace(cnt.charAt(i)))
         i++;
       if (i == cnt.length() || i == 0)
-        throw new FHIRException("Script " + name + ": Error reading include: " + cnt);
+        throw new FHIRException(engine.getWorker().formatMessage(I18nConstants.LIQUID_SYNTAX_INCLUDE, name + ": Error reading include: " + cnt));
       LiquidInclude res = new LiquidInclude();
       res.page = cnt.substring(0, i);
       while (i < cnt.length() && Character.isWhitespace(cnt.charAt(i)))
@@ -598,10 +630,10 @@ public class LiquidEngine implements IEvaluationContext {
         while (i < cnt.length() && cnt.charAt(i) != '=')
           i++;
         if (i >= cnt.length() || j == i)
-          throw new FHIRException("Script " + name + ": Error reading include: " + cnt);
+          throw new FHIRException(engine.getWorker().formatMessage(I18nConstants.LIQUID_SYNTAX_INCLUDE, name,  cnt));
         String n = cnt.substring(j, i);
         if (res.params.containsKey(n))
-          throw new FHIRException("Script " + name + ": Error reading include: " + cnt);
+          throw new FHIRException(engine.getWorker().formatMessage(I18nConstants.LIQUID_SYNTAX_INCLUDE, name,  cnt));
         i++;
         ExpressionNodeWithOffset t = engine.parsePartial(cnt, i);
         i = t.getOffset();
@@ -618,13 +650,16 @@ public class LiquidEngine implements IEvaluationContext {
         i++;
       LiquidFor res = new LiquidFor();
       res.varName = cnt.substring(0, i);
+      if ("include".equals(res.varName)) {
+        throw new FHIRException(engine.getWorker().formatMessage(I18nConstants.LIQUID_VARIABLE_ILLEGAL, res.varName));
+      }
       while (Character.isWhitespace(cnt.charAt(i)))
         i++;
       int j = i;
       while (!Character.isWhitespace(cnt.charAt(i)))
         i++;
       if (!"in".equals(cnt.substring(j, i)))
-        throw new FHIRException("Script " + name + ": Script " + name + ": Error reading loop: " + cnt);
+        throw new FHIRException(engine.getWorker().formatMessage(I18nConstants.LIQUID_SYNTAX_LOOP, name, cnt));
       res.condition = cnt.substring(i).trim();
       parseList(res.body, false, new String[] { "endloop" });
       return res;
@@ -636,13 +671,16 @@ public class LiquidEngine implements IEvaluationContext {
         i++;
       LiquidFor res = new LiquidFor();
       res.varName = cnt.substring(0, i);
+      if ("include".equals(res.varName)) {
+        throw new FHIRException(engine.getWorker().formatMessage(I18nConstants.LIQUID_VARIABLE_ILLEGAL, res.varName));
+      }
       while (Character.isWhitespace(cnt.charAt(i)))
         i++;
       int j = i;
       while (!Character.isWhitespace(cnt.charAt(i)))
         i++;
       if (!"in".equals(cnt.substring(j, i)))
-        throw new FHIRException("Script " + name + ": Script " + name + ": Error reading loop: " + cnt);
+        throw new FHIRException(engine.getWorker().formatMessage(I18nConstants.LIQUID_SYNTAX_LOOP, name, cnt));
       res.condition = cnt.substring(i).trim();
       String term = parseList(res.body, true, new String[] { "endfor", "else" });
       if ("else".equals(term)) {
@@ -651,6 +689,21 @@ public class LiquidEngine implements IEvaluationContext {
       return res;
     }
 
+    private LiquidNode parseAssign(String cnt) throws FHIRException {
+      int i = 0;
+      while (!Character.isWhitespace(cnt.charAt(i)))
+        i++;
+      LiquidAssign res = new LiquidAssign();
+      res.varName = cnt.substring(0, i);
+      while (Character.isWhitespace(cnt.charAt(i)))
+        i++;
+      int j = i;
+      while (!Character.isWhitespace(cnt.charAt(i)))
+        i++;
+      res.expression = cnt.substring(i).trim();
+      return res;
+    }
+
     private String parseTag(char ch) throws FHIRException {
       grab();
       grab();
@@ -659,7 +712,7 @@ public class LiquidEngine implements IEvaluationContext {
         b.append(grab());
       }
       if (!(next1() == '%' && next2() == '}'))
-        throw new FHIRException("Script " + name + ": Unterminated Liquid statement {% " + b.toString());
+        throw new FHIRException(engine.getWorker().formatMessage(I18nConstants.LIQUID_SYNTAX_NOTERM, name,  "{% " + b.toString()));
       grab();
       grab();
       return b.toString().trim();
@@ -673,7 +726,7 @@ public class LiquidEngine implements IEvaluationContext {
         b.append(grab());
       }
       if (!(next1() == '}' && next2() == '}'))
-        throw new FHIRException("Script " + name + ": Unterminated Liquid statement {{ " + b.toString());
+        throw new FHIRException(engine.getWorker().formatMessage(I18nConstants.LIQUID_SYNTAX_NOTERM, name,  "{{ " + b.toString()));
       grab();
       grab();
       LiquidStatement res = new LiquidStatement();
@@ -686,8 +739,10 @@ public class LiquidEngine implements IEvaluationContext {
   @Override
   public List<Base> resolveConstant(Object appContext, String name, boolean beforeContext) throws PathEngineException {
     LiquidEngineContext ctxt = (LiquidEngineContext) appContext;
-    if (ctxt.vars.containsKey(name))
+    if (ctxt.loopVars.containsKey(name))
-      return new ArrayList<Base>(Arrays.asList(ctxt.vars.get(name)));
+      return new ArrayList<Base>(Arrays.asList(ctxt.loopVars.get(name)));
+    if (ctxt.globalVars.containsKey(name))
+      return new ArrayList<Base>(Arrays.asList(ctxt.globalVars.get(name)));
     if (externalHostServices == null)
       return new ArrayList<Base>();
     return externalHostServices.resolveConstant(ctxt.externalContext, name, beforeContext);
@@ -716,8 +771,7 @@ public class LiquidEngine implements IEvaluationContext {
   }
 
   @Override
-  public TypeDetails checkFunction(Object appContext, String functionName, List<TypeDetails> parameters)
+  public TypeDetails checkFunction(Object appContext, String functionName, List<TypeDetails> parameters) throws PathEngineException {
-      throws PathEngineException {
     if (externalHostServices == null)
       return null;
     LiquidEngineContext ctxt = (LiquidEngineContext) appContext;
@@ -725,8 +779,7 @@ public class LiquidEngine implements IEvaluationContext {
   }
 
   @Override
-  public List<Base> executeFunction(Object appContext, List<Base> focus, String functionName,
+  public List<Base> executeFunction(Object appContext, List<Base> focus, String functionName, List<List<Base>> parameters) {
-      List<List<Base>> parameters) {
     if (externalHostServices == null)
       return null;
     LiquidEngineContext ctxt = (LiquidEngineContext) appContext;

org.hl7.fhir.r4b/src/main/java/org/hl7/fhir/r4b/utils/structuremap/StructureMapUtilities.java

@@ -713,7 +713,7 @@ public class StructureMapUtilities {
   }
 
   public StructureMap parse(String text, String srcName) throws FHIRException {
-    FHIRLexer lexer = new FHIRLexer(text, srcName);
+    FHIRLexer lexer = new FHIRLexer(text, srcName, true, true);
     if (lexer.done())
       throw lexer.error("Map Input cannot be empty");
     lexer.token("map");

org.hl7.fhir.r5/src/main/java/org/hl7/fhir/r5/model/ExpressionNode.java

@@ -359,6 +359,10 @@ public class ExpressionNode {
 
   public enum CollectionStatus {
     SINGLETON, ORDERED, UNORDERED;
+
+    boolean isList() {
+      return this == ORDERED || this == UNORDERED;
+    }
   }
   
   //the expression will have one of either name or constant

org.hl7.fhir.r5/src/main/java/org/hl7/fhir/r5/model/TypeDetails.java

@@ -285,7 +285,7 @@ public class TypeDetails {
   public void update(TypeDetails source) {
     for (ProfiledType pt : source.types)
       addType(pt);
-    if (collectionStatus == null)
+    if (collectionStatus == null || collectionStatus == CollectionStatus.SINGLETON)
       collectionStatus = source.collectionStatus;
     else if (source.collectionStatus == CollectionStatus.UNORDERED)
       collectionStatus = source.collectionStatus;
@@ -516,5 +516,8 @@ public class TypeDetails {
   public static TypeDetails empty() {
     return new TypeDetails(CollectionStatus.SINGLETON);
   }
+  public boolean isList() {
+    return collectionStatus != null && collectionStatus.isList();
+  }
   
 }

org.hl7.fhir.r5/src/main/java/org/hl7/fhir/r5/terminologies/validation/ValueSetValidator.java

@@ -643,7 +643,7 @@ public class ValueSetValidator extends ValueSetProcessBase {
 
   private boolean checkExpansion(Coding code, List<ValueSetExpansionContainsComponent> contains, VersionInfo vi) {
     for (ValueSetExpansionContainsComponent containsComponent: contains) {
-      if (containsComponent.getSystem().equals(code.getSystem()) && containsComponent.getCode().equals(code.getCode())) {
+      if (containsComponent.hasSystem() && containsComponent.hasCode() && containsComponent.getSystem().equals(code.getSystem()) && containsComponent.getCode().equals(code.getCode())) {
         vi.setExpansionVersion(containsComponent.getVersion());
         return true;
       }

org.hl7.fhir.r5/src/main/java/org/hl7/fhir/r5/utils/FHIRPathEngine.java

@@ -281,6 +281,7 @@ public class FHIRPathEngine {
   private boolean doNotEnforceAsSingletonRule;
   private boolean doNotEnforceAsCaseSensitive;
   private boolean allowDoubleQuotes;
+  private List<String> typeWarnings = new ArrayList<>();
 
   // if the fhir path expressions are allowed to use constants beyond those defined in the specification
   // the application can implement them by providing a constant resolver 
@@ -656,7 +657,8 @@ public class FHIRPathEngine {
    * @throws PathEngineException 
    * @if the path is not valid
    */
-  public TypeDetails checkOnTypes(Object appContext, String resourceType, List<String> typeList, ExpressionNode expr) throws FHIRLexerException, PathEngineException, DefinitionException {
+  public TypeDetails checkOnTypes(Object appContext, String resourceType, List<String> typeList, ExpressionNode expr, List<String> warnings) throws FHIRLexerException, PathEngineException, DefinitionException {
+    typeWarnings.clear();
 
     // if context is a path that refers to a type, do that conversion now 
     TypeDetails types = new TypeDetails(CollectionStatus.SINGLETON);
@@ -689,7 +691,9 @@ public class FHIRPathEngine {
         }
       }
     }
-    return executeType(new ExecutionTypeContext(appContext, resourceType, types, types), types, expr, null, true, false);
+    TypeDetails res = executeType(new ExecutionTypeContext(appContext, resourceType, types, types), types, expr, null, true, false);
+    warnings.addAll(typeWarnings);
+    return res;
   }
   
   /**
@@ -2017,18 +2021,54 @@ public class FHIRPathEngine {
   }
 
 
+  private void checkCardinalityForComparabilitySame(TypeDetails left, Operation operation, TypeDetails right, ExpressionNode expr) {
+    if (left.isList() && !right.isList()) {
+      typeWarnings.add(worker.formatMessage(I18nConstants.FHIRPATH_COLLECTION_STATUS_OPERATION_LEFT, expr.toString()));
+    } else if (!left.isList() && right.isList()) {
+      typeWarnings.add(worker.formatMessage(I18nConstants.FHIRPATH_COLLECTION_STATUS_OPERATION_RIGHT, expr.toString()));
+    }
+  }
+
+  private void checkCardinalityForSingle(TypeDetails left, Operation operation, TypeDetails right, ExpressionNode expr) {
+    if (left.isList()) {
+      typeWarnings.add(worker.formatMessage(I18nConstants.FHIRPATH_COLLECTION_STATUS_OPERATION_LEFT, expr.toString()));
+    } 
+    if (right.isList()) {
+      typeWarnings.add(worker.formatMessage(I18nConstants.FHIRPATH_COLLECTION_STATUS_OPERATION_RIGHT, expr.toString()));
+    }
+  }
+  
   private TypeDetails operateTypes(TypeDetails left, Operation operation, TypeDetails right, ExpressionNode expr) {
     switch (operation) {
-    case Equals: return new TypeDetails(CollectionStatus.SINGLETON, TypeDetails.FP_Boolean);
+    case Equals: 
-    case Equivalent: return new TypeDetails(CollectionStatus.SINGLETON, TypeDetails.FP_Boolean);
+      checkCardinalityForComparabilitySame(left, operation, right, expr);
-    case NotEquals: return new TypeDetails(CollectionStatus.SINGLETON, TypeDetails.FP_Boolean);
+      return new TypeDetails(CollectionStatus.SINGLETON, TypeDetails.FP_Boolean);
-    case NotEquivalent: return new TypeDetails(CollectionStatus.SINGLETON, TypeDetails.FP_Boolean);
+    case Equivalent: 
-    case LessThan: return new TypeDetails(CollectionStatus.SINGLETON, TypeDetails.FP_Boolean);
+      checkCardinalityForComparabilitySame(left, operation, right, expr);
-    case Greater: return new TypeDetails(CollectionStatus.SINGLETON, TypeDetails.FP_Boolean);
+      return new TypeDetails(CollectionStatus.SINGLETON, TypeDetails.FP_Boolean);
-    case LessOrEqual: return new TypeDetails(CollectionStatus.SINGLETON, TypeDetails.FP_Boolean);
+    case NotEquals: 
-    case GreaterOrEqual: return new TypeDetails(CollectionStatus.SINGLETON, TypeDetails.FP_Boolean);
+      checkCardinalityForComparabilitySame(left, operation, right, expr);
-    case Is: return new TypeDetails(CollectionStatus.SINGLETON, TypeDetails.FP_Boolean);
+      return new TypeDetails(CollectionStatus.SINGLETON, TypeDetails.FP_Boolean);
+    case NotEquivalent: 
+      checkCardinalityForComparabilitySame(left, operation, right, expr);
+      return new TypeDetails(CollectionStatus.SINGLETON, TypeDetails.FP_Boolean);
+    case LessThan: 
+      checkCardinalityForSingle(left, operation, right, expr);
+      return new TypeDetails(CollectionStatus.SINGLETON, TypeDetails.FP_Boolean);
+    case Greater: 
+      checkCardinalityForSingle(left, operation, right, expr);
+      return new TypeDetails(CollectionStatus.SINGLETON, TypeDetails.FP_Boolean);
+    case LessOrEqual: 
+      checkCardinalityForSingle(left, operation, right, expr);
+      return new TypeDetails(CollectionStatus.SINGLETON, TypeDetails.FP_Boolean);
+    case GreaterOrEqual: 
+      checkCardinalityForSingle(left, operation, right, expr);
+      return new TypeDetails(CollectionStatus.SINGLETON, TypeDetails.FP_Boolean);
+    case Is: 
+      checkCardinalityForSingle(left, operation, right, expr);
+      return new TypeDetails(CollectionStatus.SINGLETON, TypeDetails.FP_Boolean);
     case As: 
+      checkCardinalityForSingle(left, operation, right, expr);
       TypeDetails td = new TypeDetails(CollectionStatus.SINGLETON, right.getTypes());
       if (td.typesHaveTargets()) {
         td.addTargets(left.getTargets());
@@ -2040,6 +2080,7 @@ public class FHIRPathEngine {
     case Xor: return new TypeDetails(CollectionStatus.SINGLETON, TypeDetails.FP_Boolean);
     case Implies : return new TypeDetails(CollectionStatus.SINGLETON, TypeDetails.FP_Boolean);
     case Times: 
+      checkCardinalityForSingle(left, operation, right, expr);
       TypeDetails result = new TypeDetails(CollectionStatus.SINGLETON);
       if (left.hasType(worker, "integer") && right.hasType(worker, "integer")) {
         result.addType(TypeDetails.FP_Integer);
@@ -2048,6 +2089,7 @@ public class FHIRPathEngine {
       }
       return result;
     case DivideBy: 
+      checkCardinalityForSingle(left, operation, right, expr);
       result = new TypeDetails(CollectionStatus.SINGLETON);
       if (left.hasType(worker, "integer") && right.hasType(worker, "integer")) {
         result.addType(TypeDetails.FP_Decimal);
@@ -2056,9 +2098,11 @@ public class FHIRPathEngine {
       }
       return result;
     case Concatenate:
+      checkCardinalityForSingle(left, operation, right, expr);
       result = new TypeDetails(CollectionStatus.SINGLETON, TypeDetails.FP_String);
       return result;
     case Plus:
+      checkCardinalityForSingle(left, operation, right, expr);
       result = new TypeDetails(CollectionStatus.SINGLETON);
       if (left.hasType(worker, "integer") && right.hasType(worker, "integer")) {
         result.addType(TypeDetails.FP_Integer);
@@ -2075,6 +2119,7 @@ public class FHIRPathEngine {
       }
       return result;
     case Minus:
+      checkCardinalityForSingle(left, operation, right, expr);
       result = new TypeDetails(CollectionStatus.SINGLETON);
       if (left.hasType(worker, "integer") && right.hasType(worker, "integer")) {
         result.addType(TypeDetails.FP_Integer);
@@ -2092,6 +2137,7 @@ public class FHIRPathEngine {
       return result;
     case Div: 
     case Mod: 
+      checkCardinalityForSingle(left, operation, right, expr);
       result = new TypeDetails(CollectionStatus.SINGLETON);
       if (left.hasType(worker, "integer") && right.hasType(worker, "integer")) {
         result.addType(TypeDetails.FP_Integer);
@@ -3222,7 +3268,7 @@ public class FHIRPathEngine {
     if (atEntry && Character.isUpperCase(exp.getName().charAt(0)) && hashTail(type).equals(exp.getName())) { // special case for start up
       return new TypeDetails(CollectionStatus.SINGLETON, type);
     }
-    TypeDetails result = new TypeDetails(null);
+    TypeDetails result = new TypeDetails(focus.getCollectionStatus());
     getChildTypesByName(type, exp.getName(), result, exp, focus, elementDependencies);
     return result;
   }
@@ -3265,6 +3311,10 @@ public class FHIRPathEngine {
       } while (changed);
       paramTypes.clear();
       paramTypes.add(base);
+    } else if (exp.getFunction() == Function.Where || exp.getFunction() == Function.Select || exp.getFunction() == Function.Exists || 
+        exp.getFunction() == Function.All || exp.getFunction() == Function.AllTrue || exp.getFunction() == Function.AnyTrue 
+        || exp.getFunction() == Function.AllFalse || exp.getFunction() == Function.AnyFalse) {
+      evaluateParameters(context, focus.toSingleton(), exp, elementDependencies, paramTypes, false);
     } else {
       evaluateParameters(context, focus, exp, elementDependencies, paramTypes, false);
     }

org.hl7.fhir.r5/src/main/java/org/hl7/fhir/r5/utils/LiquidEngine.java

@@ -47,6 +47,7 @@ import org.hl7.fhir.r5.model.ValueSet;
 import org.hl7.fhir.r5.utils.FHIRPathEngine.ExpressionNodeWithOffset;
 import org.hl7.fhir.r5.utils.FHIRPathEngine.IEvaluationContext;
 import org.hl7.fhir.utilities.Utilities;
+import org.hl7.fhir.utilities.i18n.I18nConstants;
 import org.hl7.fhir.utilities.xhtml.NodeType;
 import org.hl7.fhir.utilities.xhtml.XhtmlNode;
 
@@ -67,17 +68,27 @@ public class LiquidEngine implements IEvaluationContext {
 
   private class LiquidEngineContext {
     private Object externalContext;
-    private Map<String, Base> vars = new HashMap<>();
+    private Map<String, Base> loopVars = new HashMap<>();
+    private Map<String, Base> globalVars = new HashMap<>();
 
     public LiquidEngineContext(Object externalContext) {
       super();
       this.externalContext = externalContext;
+      globalVars = new HashMap<>();
+    }
+
+    public LiquidEngineContext(Object externalContext, LiquidEngineContext existing) {
+      super();
+      this.externalContext = externalContext;
+      loopVars.putAll(existing.loopVars);
+      globalVars = existing.globalVars;
     }
 
     public LiquidEngineContext(LiquidEngineContext existing) {
       super();
       externalContext = existing.externalContext;
-      vars.putAll(existing.vars);
+      loopVars.putAll(existing.loopVars);
+      globalVars = existing.globalVars;
     }
   }
 
@@ -185,7 +196,7 @@ public class LiquidEngine implements IEvaluationContext {
             String f = lexer.getCurrent();
             LiquidFilter filter = LiquidFilter.fromCode(f);
             if (filter == null) {
-              lexer.error("Unknown Liquid filter '"+f+"'");
+              lexer.error(engine.getWorker().formatMessage(I18nConstants.LIQUID_UNKNOWN_FILTER, f));
             }
             lexer.next();
             if (!lexer.done() && lexer.getCurrent().equals(":")) {
@@ -195,7 +206,7 @@ public class LiquidEngine implements IEvaluationContext {
               compiled.add(new LiquidExpressionNode(filter, null));
             }
           } else {
-            lexer.error("Unexpected syntax parsing liquid statement");
+            lexer.error(engine.getWorker().formatMessage(I18nConstants.LIQUID_UNKNOWN_SYNTAX)); 
           }
         }
       }
@@ -305,6 +316,30 @@ public class LiquidEngine implements IEvaluationContext {
     }
   }
 
+  private class LiquidAssign extends LiquidNode {
+    private String varName;
+    private String expression;
+    private ExpressionNode compiled;
+    @Override
+    public void evaluate(StringBuilder b, Base resource, LiquidEngineContext ctxt) throws FHIRException {
+      if (compiled == null) {
+        boolean dbl = engine.isAllowDoubleQuotes();
+        engine.setAllowDoubleQuotes(true);
+        ExpressionNodeWithOffset po = engine.parsePartial(expression, 0);
+        compiled = po.getNode();
+        engine.setAllowDoubleQuotes(dbl);
+      }
+      List<Base> list = engine.evaluate(ctxt, resource, resource, resource, compiled);
+      if (list.isEmpty()) {
+        ctxt.globalVars.remove(varName);
+      } else if (list.size() == 1) {
+        ctxt.globalVars.put(varName, list.get(0));
+      } else {
+        throw new Error("Assign returned a list?");
+      }      
+    }    
+  }
+  
   private class LiquidFor extends LiquidNode {
     private String varName;
     private String condition;
@@ -343,7 +378,10 @@ public class LiquidEngine implements IEvaluationContext {
           if (limit >= 0 && i == limit) {
             break;
           }          
-          lctxt.vars.put(varName, o);
+          if (lctxt.globalVars.containsKey(varName)) {
+            throw new FHIRException(engine.getWorker().formatMessage(I18nConstants.LIQUID_VARIABLE_ALREADY_ASSIGNED, varName));
+          }
+          lctxt.loopVars.put(varName, o);
           boolean wantBreak = false;
           for (LiquidNode n : body) {
             try {
@@ -372,7 +410,7 @@ public class LiquidEngine implements IEvaluationContext {
         } else if (cnt.startsWith("limit")) {
           cnt = cnt.substring(5).trim();
           if (!cnt.startsWith(":")) {
-            throw new FHIRException("Exception evaluating "+src+": limit is not followed by ':'");
+            throw new FHIRException(engine.getWorker().formatMessage(I18nConstants.LIQUID_SYNTAX_COLON, src));
           }
           cnt = cnt.substring(1).trim();
           int i = 0;
@@ -380,14 +418,14 @@ public class LiquidEngine implements IEvaluationContext {
             i++;
           }
           if (i == 0) {
-            throw new FHIRException("Exception evaluating "+src+": limit is not followed by a number");
+            throw new FHIRException(engine.getWorker().formatMessage(I18nConstants.LIQUID_SYNTAX_NUMBER, src));
           }
           limit = Integer.parseInt(cnt.substring(0, i));
           cnt = cnt.substring(i);
         } else if (cnt.startsWith("offset")) {
           cnt = cnt.substring(6).trim();
           if (!cnt.startsWith(":")) {
-            throw new FHIRException("Exception evaluating "+src+": limit is not followed by ':'");
+            throw new FHIRException(engine.getWorker().formatMessage(I18nConstants.LIQUID_SYNTAX_COLON, src));
           }
           cnt = cnt.substring(1).trim();
           int i = 0;
@@ -395,12 +433,12 @@ public class LiquidEngine implements IEvaluationContext {
             i++;
           }
           if (i == 0) {
-            throw new FHIRException("Exception evaluating "+src+": limit is not followed by a number");
+            throw new FHIRException(engine.getWorker().formatMessage(I18nConstants.LIQUID_SYNTAX_NUMBER, src));
           }
           offset = Integer.parseInt(cnt.substring(0, i));
           cnt = cnt.substring(i);
         } else {
-          throw new FHIRException("Exception evaluating "+src+": unexpected content at "+cnt);
+          throw new FHIRException(engine.getWorker().formatMessage(I18nConstants.LIQUID_SYNTAX_UNEXPECTED, cnt));
         }
       }      
     }
@@ -415,9 +453,9 @@ public class LiquidEngine implements IEvaluationContext {
       String src = includeResolver.fetchInclude(LiquidEngine.this, page);
       LiquidParser parser = new LiquidParser(src);
       LiquidDocument doc = parser.parse(page);
-      LiquidEngineContext nctxt = new LiquidEngineContext(ctxt.externalContext);
+      LiquidEngineContext nctxt = new LiquidEngineContext(ctxt.externalContext, ctxt);
       Tuple incl = new Tuple();
-      nctxt.vars.put("include", incl);
+      nctxt.loopVars.put("include", incl);
       for (String s : params.keySet()) {
         incl.addProperty(s, engine.evaluate(ctxt, resource, resource, resource, params.get(s)));
       }
@@ -474,11 +512,11 @@ public class LiquidEngine implements IEvaluationContext {
       cnt = "," + cnt.substring(5).trim();
       while (!Utilities.noString(cnt)) {
         if (!cnt.startsWith(",")) {
-          throw new FHIRException("Script " + name + ": Script " + name + ": Found " + cnt.charAt(0) + " expecting ',' parsing cycle");
+          throw new FHIRException(engine.getWorker().formatMessage(I18nConstants.LIQUID_SYNTAX_EXPECTING, name, cnt.charAt(0), ','));
         }
         cnt = cnt.substring(1).trim();
         if (!cnt.startsWith("\"")) {
-          throw new FHIRException("Script " + name + ": Script " + name + ": Found " + cnt.charAt(0) + " expecting '\"' parsing cycle");
+          throw new FHIRException(engine.getWorker().formatMessage(I18nConstants.LIQUID_SYNTAX_EXPECTING, name, cnt.charAt(0), '"'));
         }
         cnt = cnt.substring(1);
         int i = 0;
@@ -486,7 +524,7 @@ public class LiquidEngine implements IEvaluationContext {
           i++;
         }
         if (i == cnt.length()) {
-          throw new FHIRException("Script " + name + ": Script " + name + ": Found unterminated string parsing cycle");
+          throw new FHIRException(engine.getWorker().formatMessage(I18nConstants.LIQUID_SYNTAX_UNTERMINATED, name));
         }
         res.list.add(cnt.substring(0, i));
         cnt = cnt.substring(i + 1).trim();
@@ -518,8 +556,10 @@ public class LiquidEngine implements IEvaluationContext {
               list.add(parseCycle(cnt));
             else if (cnt.startsWith("include "))
               list.add(parseInclude(cnt.substring(7).trim()));
+            else if (cnt.startsWith("assign "))
+              list.add(parseAssign(cnt.substring(6).trim()));
             else
-              throw new FHIRException("Script " + name + ": Script " + name + ": Unknown flow control statement " + cnt);
+              throw new FHIRException(engine.getWorker().formatMessage(I18nConstants.LIQUID_UNKNOWN_FLOW_STMT,name, cnt));
           } else { // next2() == '{'
             list.add(parseStatement());
           }
@@ -533,7 +573,7 @@ public class LiquidEngine implements IEvaluationContext {
         n.closeUp();
       if (terminators.length > 0)
         if (!isTerminator(close, terminators))
-          throw new FHIRException("Script " + name + ": Script " + name + ": Found end of script looking for " + terminators);
+          throw new FHIRException(engine.getWorker().formatMessage(I18nConstants.LIQUID_UNKNOWN_NOEND, name, terminators));
       return close;
     }
 
@@ -577,7 +617,7 @@ public class LiquidEngine implements IEvaluationContext {
       while (i < cnt.length() && !Character.isWhitespace(cnt.charAt(i)))
         i++;
       if (i == cnt.length() || i == 0)
-        throw new FHIRException("Script " + name + ": Error reading include: " + cnt);
+        throw new FHIRException(engine.getWorker().formatMessage(I18nConstants.LIQUID_SYNTAX_INCLUDE, name + ": Error reading include: " + cnt));
       LiquidInclude res = new LiquidInclude();
       res.page = cnt.substring(0, i);
       while (i < cnt.length() && Character.isWhitespace(cnt.charAt(i)))
@@ -587,10 +627,10 @@ public class LiquidEngine implements IEvaluationContext {
         while (i < cnt.length() && cnt.charAt(i) != '=')
           i++;
         if (i >= cnt.length() || j == i)
-          throw new FHIRException("Script " + name + ": Error reading include: " + cnt);
+          throw new FHIRException(engine.getWorker().formatMessage(I18nConstants.LIQUID_SYNTAX_INCLUDE, name,  cnt));
         String n = cnt.substring(j, i);
         if (res.params.containsKey(n))
-          throw new FHIRException("Script " + name + ": Error reading include: " + cnt);
+          throw new FHIRException(engine.getWorker().formatMessage(I18nConstants.LIQUID_SYNTAX_INCLUDE, name,  cnt));
         i++;
         ExpressionNodeWithOffset t = engine.parsePartial(cnt, i);
         i = t.getOffset();
@@ -607,13 +647,16 @@ public class LiquidEngine implements IEvaluationContext {
         i++;
       LiquidFor res = new LiquidFor();
       res.varName = cnt.substring(0, i);
+      if ("include".equals(res.varName)) {
+        throw new FHIRException(engine.getWorker().formatMessage(I18nConstants.LIQUID_VARIABLE_ILLEGAL, res.varName));
+      }
       while (Character.isWhitespace(cnt.charAt(i)))
         i++;
       int j = i;
       while (!Character.isWhitespace(cnt.charAt(i)))
         i++;
       if (!"in".equals(cnt.substring(j, i)))
-        throw new FHIRException("Script " + name + ": Script " + name + ": Error reading loop: " + cnt);
+        throw new FHIRException(engine.getWorker().formatMessage(I18nConstants.LIQUID_SYNTAX_LOOP, name, cnt));
       res.condition = cnt.substring(i).trim();
       parseList(res.body, false, new String[] { "endloop" });
       return res;
@@ -625,13 +668,16 @@ public class LiquidEngine implements IEvaluationContext {
         i++;
       LiquidFor res = new LiquidFor();
       res.varName = cnt.substring(0, i);
+      if ("include".equals(res.varName)) {
+        throw new FHIRException(engine.getWorker().formatMessage(I18nConstants.LIQUID_VARIABLE_ILLEGAL, res.varName));
+      }
       while (Character.isWhitespace(cnt.charAt(i)))
         i++;
       int j = i;
       while (!Character.isWhitespace(cnt.charAt(i)))
         i++;
       if (!"in".equals(cnt.substring(j, i)))
-        throw new FHIRException("Script " + name + ": Script " + name + ": Error reading loop: " + cnt);
+        throw new FHIRException(engine.getWorker().formatMessage(I18nConstants.LIQUID_SYNTAX_LOOP, name, cnt));
       res.condition = cnt.substring(i).trim();
       String term = parseList(res.body, true, new String[] { "endfor", "else" });
       if ("else".equals(term)) {
@@ -640,6 +686,20 @@ public class LiquidEngine implements IEvaluationContext {
       return res;
     }
 
+    private LiquidNode parseAssign(String cnt) throws FHIRException {
+      int i = 0;
+      while (!Character.isWhitespace(cnt.charAt(i)))
+        i++;
+      LiquidAssign res = new LiquidAssign();
+      res.varName = cnt.substring(0, i);
+      while (Character.isWhitespace(cnt.charAt(i)))
+        i++;
+      int j = i;
+      while (!Character.isWhitespace(cnt.charAt(i)))
+        i++;
+      res.expression = cnt.substring(i).trim();
+      return res;
+    }
 
     private String parseTag(char ch) throws FHIRException {
       grab();
@@ -649,7 +709,7 @@ public class LiquidEngine implements IEvaluationContext {
         b.append(grab());
       }
       if (!(next1() == '%' && next2() == '}'))
-        throw new FHIRException("Script " + name + ": Unterminated Liquid statement {% " + b.toString());
+        throw new FHIRException(engine.getWorker().formatMessage(I18nConstants.LIQUID_SYNTAX_NOTERM, name,  "{% " + b.toString()));
       grab();
       grab();
       return b.toString().trim();
@@ -663,7 +723,7 @@ public class LiquidEngine implements IEvaluationContext {
         b.append(grab());
       }
       if (!(next1() == '}' && next2() == '}'))
-        throw new FHIRException("Script " + name + ": Unterminated Liquid statement {{ " + b.toString());
+        throw new FHIRException(engine.getWorker().formatMessage(I18nConstants.LIQUID_SYNTAX_NOTERM, name,  "{{ " + b.toString()));
       grab();
       grab();
       LiquidStatement res = new LiquidStatement();
@@ -676,8 +736,10 @@ public class LiquidEngine implements IEvaluationContext {
   @Override
   public List<Base> resolveConstant(Object appContext, String name, boolean beforeContext) throws PathEngineException {
     LiquidEngineContext ctxt = (LiquidEngineContext) appContext;
-    if (ctxt.vars.containsKey(name))
+    if (ctxt.loopVars.containsKey(name))
-      return new ArrayList<Base>(Arrays.asList(ctxt.vars.get(name)));
+      return new ArrayList<Base>(Arrays.asList(ctxt.loopVars.get(name)));
+    if (ctxt.globalVars.containsKey(name))
+      return new ArrayList<Base>(Arrays.asList(ctxt.globalVars.get(name)));
     if (externalHostServices == null)
       return new ArrayList<Base>();
     return externalHostServices.resolveConstant(ctxt.externalContext, name, beforeContext);

org.hl7.fhir.r5/src/test/java/org/hl7/fhir/r5/formats/UnicodeCharacterTests.java

@@ -0,0 +1,44 @@
+package org.hl7.fhir.r5.formats;
+
+import java.io.FileInputStream;
+import java.io.FileOutputStream;
+import java.io.IOException;
+
+import org.hl7.fhir.exceptions.FHIRFormatError;
+import org.hl7.fhir.r5.formats.IParser.OutputStyle;
+import org.hl7.fhir.r5.model.Parameters;
+import org.hl7.fhir.r5.test.utils.TestingUtilities;
+import org.hl7.fhir.utilities.Utilities;
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.Test;
+
+public class UnicodeCharacterTests {
+
+  @Test
+  public void testUnicodeXml() throws FHIRFormatError, IOException {
+    XmlParser xml = new XmlParser();
+    xml.setOutputStyle(OutputStyle.PRETTY);
+    Parameters p = (Parameters) xml.parse(TestingUtilities.loadTestResource("r5", "unicode-problem.xml"));
+    Assertions.assertEquals("invalid: \u0013, not invalid: \r", p.getParameterFirstRep().getValue().primitiveValue());
+    FileOutputStream o = new FileOutputStream(Utilities.path("[tmp]", "unicode-problem.xml"));
+    xml.compose(o, p);
+    o.close();
+    p = (Parameters) xml.parse(new FileInputStream(Utilities.path("[tmp]", "unicode-problem.xml")));
+    Assertions.assertEquals("invalid: \u0013, not invalid: \r", p.getParameterFirstRep().getValue().primitiveValue());
+  }
+  
+
+  @Test
+  public void testUnicodeJson() throws FHIRFormatError, IOException {
+    JsonParser json = new JsonParser();
+    json.setOutputStyle(OutputStyle.PRETTY);
+    Parameters p = (Parameters) json.parse(TestingUtilities.loadTestResource("r5", "unicode-problem.json"));
+    Assertions.assertEquals("invalid: \u0013, not invalid: \r", p.getParameterFirstRep().getValue().primitiveValue());
+    FileOutputStream o = new FileOutputStream(Utilities.path("[tmp]", "unicode-problem.json"));
+    json.compose(o, p);
+    o.close();
+    p = (Parameters) json.parse(new FileInputStream(Utilities.path("[tmp]", "unicode-problem.json")));
+    Assertions.assertEquals("invalid: \u0013, not invalid: \r", p.getParameterFirstRep().getValue().primitiveValue());
+  }
+  
+}

org.hl7.fhir.utilities/src/main/java/org/hl7/fhir/utilities/Utilities.java

@@ -984,7 +984,7 @@ public class Utilities {
       else if (isWhitespace(c)) {
         b.append("\\u"+Utilities.padLeft(Integer.toHexString(c), '0', 4));
       } else if (((int) c) < 32)
-        b.append("\\u" + Utilities.padLeft(String.valueOf((int) c), '0', 4));
+        b.append("\\u" + Utilities.padLeft(Integer.toHexString(c), '0', 4));
       else
         b.append(c);
     }

org.hl7.fhir.utilities/src/main/java/org/hl7/fhir/utilities/i18n/I18nConstants.java

@@ -926,6 +926,28 @@ public class I18nConstants {
   public static final String VALUESET_CONCEPT_DISPLAY_PRESENCE_MIXED = "VALUESET_CONCEPT_DISPLAY_PRESENCE_MIXED";
   public static final String VALUESET_CONCEPT_DISPLAY_SCT_TAG_MIXED = "VALUESET_CONCEPT_DISPLAY_SCT_TAG_MIXED";
   public static final String CS_SCT_IPS_NOT_IPS = "CS_SCT_IPS_NOT_IPS";
+  public static final String UNICODE_XML_BAD_CHARS = "UNICODE_XML_BAD_CHARS";
+  public static final String LIQUID_UNKNOWN_FILTER = "LIQUID_UNKNOWN_FILTER";
+  public static final String LIQUID_UNKNOWN_SYNTAX = "LIQUID_UNKNOWN_SYNTAX";
+  public static final String LIQUID_SYNTAX_EXPECTING = "LIQUID_SYNTAX_EXPECTING";
+  public static final String LIQUID_SYNTAX_UNTERMINATED = "LIQUID_SYNTAX_UNTERMINATED";
+  public static final String LIQUID_UNKNOWN_FLOW_STMT = "LIQUID_UNKNOWN_FLOW_STMT";
+  public static final String LIQUID_UNKNOWN_NOEND = "LIQUID_UNKNOWN_NOEND";
+  public static final String LIQUID_SYNTAX_INCLUDE = "LIQUID_SYNTAX_INCLUDE";
+  public static final String LIQUID_SYNTAX_LOOP = "LIQUID_SYNTAX_LOOP";
+  public static final String LIQUID_SYNTAX_NOTERM = "LIQUID_SYNTAX_NOTERM";
+  public static final String LIQUID_UNKNOWN_NOTERM = "LIQUID_UNKNOWN_NOTERM";
+  public static final String LIQUID_SYNTAX_COLON = "LIQUID_SYNTAX_COLON";
+  public static final String LIQUID_SYNTAX_NUMBER = "LIQUID_SYNTAX_NUMBER";
+  public static final String LIQUID_SYNTAX_UNEXPECTED = "LIQUID_SYNTAX_UNEXPECTED";
+  public static final String LIQUID_VARIABLE_ALREADY_ASSIGNED = "LIQUID_VARIABLE_ALREADY_ASSIGNED";
+  public static final String LIQUID_VARIABLE_ILLEGAL = "LIQUID_VARIABLE_ILLEGAL";
+  public static final String TERMINOLOGY_TX_SYSTEM_NOT_USABLE = "TERMINOLOGY_TX_SYSTEM_NOT_USABLE";
+  public static final String ED_INVARIANT_DIFF_NO_SOURCE = "ED_INVARIANT_DIFF_NO_SOURCE";
+  public static final String FHIRPATH_COLLECTION_STATUS_OPERATION_LEFT = "FHIRPATH_COLLECTION_STATUS_OPERATION_LEFT";
+  public static final String FHIRPATH_COLLECTION_STATUS_OPERATION_RIGHT = "FHIRPATH_COLLECTION_STATUS_OPERATION_RIGHT";
+
+
 
 }
 

org.hl7.fhir.utilities/src/main/java/org/hl7/fhir/utilities/npm/NpmPackage.java

@@ -462,7 +462,7 @@ public class NpmPackage {
 
       while ((entry = (TarArchiveEntry) tarIn.getNextEntry()) != null) {
         String n = entry.getName();
-        if (n.contains("..")) {
+        if (n.contains("/..") || n.contains("../")) {
           throw new RuntimeException("Entry with an illegal name: " + n);
         }
         if (entry.isDirectory()) {

org.hl7.fhir.utilities/src/main/resources/Messages.properties

@@ -184,6 +184,7 @@ Terminology_TX_NoValid_8 = None of the codes provided are in the maximum value s
 Terminology_TX_NoValid_9 = The code provided ({2}) could not be validated against the maximum value set {0}, (error = {1})
 Terminology_TX_System_Invalid = Invalid System URI: {0}
 Terminology_TX_System_NotKnown = Code System URI ''{0}'' is unknown so the code cannot be validated
+TERMINOLOGY_TX_SYSTEM_NOT_USABLE = The definition for the Code System with URI ''{0}'' doesn't provide any codes so the code cannot be validated
 Terminology_TX_System_Relative = Coding.system must be an absolute reference, not a local reference
 Terminology_TX_System_Unknown = Unknown Code System ''{0}''
 Terminology_TX_System_ValueSet = Invalid System URI: {0} - cannot use a value set URI as a system
@@ -981,3 +982,23 @@ SD_ED_TYPE_WRONG_TYPE_other = The element has a type {0} which is not in the typ
 VALUESET_CONCEPT_DISPLAY_PRESENCE_MIXED = This include has some concepts with displays and some without - check that this is what is intended
 VALUESET_CONCEPT_DISPLAY_SCT_TAG_MIXED = This SNOMED-CT based include has some concepts with semantic tags (FSN terms) and some without (preferred terms) - check that this is what is intended
 CS_SCT_IPS_NOT_IPS = The Snomed CT code {0} ({1}) is not a member of the IPS free set
+UNICODE_XML_BAD_CHARS_one = This content includes the character {1} (hex value). This character is illegal in the XML version of FHIR, and there is generally no valid use for such characters
+UNICODE_XML_BAD_CHARS_other = This content includes the characters {1} (hex values). These characters are illegal in the XML version of FHIR, and there is generally no valid use for such characters
+LIQUID_UNKNOWN_FILTER = Unknown Liquid filter '''{0}''
+LIQUID_UNKNOWN_SYNTAX = Unexpected syntax parsing liquid statement
+LIQUID_SYNTAX_EXPECTING = Script {0}: Found ''{1}'' expecting ''{2}'' parsing cycle
+LIQUID_SYNTAX_UNTERMINATED = Script {0}: Found unterminated string parsing cycle
+LIQUID_UNKNOWN_FLOW_STMT = Script {0}: Unknown flow control statement ''{1}''
+LIQUID_UNKNOWN_NOEND = Script {0}: Found end of script looking for {1}
+LIQUID_SYNTAX_INCLUDE = Script {0}: Error reading include: {1}
+LIQUID_SYNTAX_LOOP = Script {0}: Error reading loop: {1}
+LIQUID_SYNTAX_NOTERM = Script {0}: Unterminated Liquid statement {1}
+LIQUID_UNKNOWN_NOTERM = Script {0}: Unterminated Liquid statement {1}
+LIQUID_SYNTAX_COLON = Exception evaluating {0}: limit is not followed by '':''
+LIQUID_SYNTAX_NUMBER = Exception evaluating {0}: limit is not followed by a number
+LIQUID_SYNTAX_UNEXPECTED = Exception evaluating {0}: unexpected content at {1}
+LIQUID_VARIABLE_ALREADY_ASSIGNED = Liquid Exception: The variable ''{0}'' already has an assigned value
+LIQUID_VARIABLE_ILLEGAL = Liquid Exception: The variable name ''{0}'' cannot be used
+ED_INVARIANT_DIFF_NO_SOURCE = The invariant {0} defined in the differential must have no source, or the source must be the same as the profile
+FHIRPATH_COLLECTION_STATUS_OPERATION_LEFT = The left side is inherently a collection, and so the expression ''{0}'' may fail or return false if there is more than one item in the content being evaluated
+FHIRPATH_COLLECTION_STATUS_OPERATION_RIGHT = The right side is inherently a collection, and so this expression ''{0}'' may fail or return false if there is more than one item in the content being evaluated

org.hl7.fhir.utilities/src/main/resources/Messages_es.properties

@@ -829,3 +829,6 @@ NO_VALID_DISPLAY_FOUND_other =
 PRIMITIVE_VALUE_ALTERNATIVES_MESSAGE_one = 
 PRIMITIVE_VALUE_ALTERNATIVES_MESSAGE_many = 
 PRIMITIVE_VALUE_ALTERNATIVES_MESSAGE_other =
+UNICODE_XML_BAD_CHARS_one = 
+UNICODE_XML_BAD_CHARS_many = 
+UNICODE_XML_BAD_CHARS_other = 

org.hl7.fhir.validation/src/main/java/org/hl7/fhir/validation/instance/InstanceValidator.java

@@ -113,6 +113,7 @@ import org.hl7.fhir.r5.model.ElementDefinition.PropertyRepresentation;
 import org.hl7.fhir.r5.model.ElementDefinition.TypeRefComponent;
 import org.hl7.fhir.r5.model.Enumeration;
 import org.hl7.fhir.r5.model.Enumerations.BindingStrength;
+import org.hl7.fhir.r5.model.Enumerations.CodeSystemContentMode;
 import org.hl7.fhir.r5.model.ExpressionNode;
 import org.hl7.fhir.r5.model.ExpressionNode.CollectionStatus;
 import org.hl7.fhir.r5.model.Extension;
@@ -1075,7 +1076,14 @@ public class InstanceValidator extends BaseValidator implements IResourceValidat
           }           
         } 
         if (!isAllowExamples() || !Utilities.startsWithInList(system, "http://example.org", "https://example.org")) {
+          CodeSystem cs = context.fetchCodeSystem(system);
+          if (cs == null) {
             hint(errors, NO_RULE_DATE, IssueType.UNKNOWN, element.line(), element.col(), path, done, I18nConstants.TERMINOLOGY_TX_SYSTEM_NOTKNOWN, system);
+          } else {
+            if (hint(errors, NO_RULE_DATE, IssueType.UNKNOWN, element.line(), element.col(), path, cs.getContent() != CodeSystemContentMode.NOTPRESENT, I18nConstants.TERMINOLOGY_TX_SYSTEM_NOT_USABLE, system)) {
+              rule(errors, NO_RULE_DATE, IssueType.UNKNOWN, element.line(), element.col(), path, false, "Error - this should not happen? (Consult GG)"); 
+            }
+          }
         }
         return true;
       } catch (Exception e) {
@@ -2379,6 +2387,14 @@ public class InstanceValidator extends BaseValidator implements IResourceValidat
           ok = false;
         }
       }
+      Set<String> badChars = new HashSet<>();
+      for (char ch : e.primitiveValue().toCharArray()) {
+        if (ch < 32 && !(ch == '\r' || ch == '\n' || ch == '\t')) {
+          // can't get to here with xml - the parser fails if you try
+          badChars.add(Integer.toHexString(ch));
+        }        
+      }
+      warningPlural(errors, "2023-07-26", IssueType.INVALID, e.line(), e.col(), path, badChars.isEmpty(), badChars.size(), I18nConstants.UNICODE_XML_BAD_CHARS, badChars.toString());      
     }
     String regex = context.getExtensionString(ToolingExtensions.EXT_REGEX);
     // there's a messy history here - this extension snhould only be on the element definition itself, but for historical reasons 

org.hl7.fhir.validation/src/main/java/org/hl7/fhir/validation/instance/type/StructureDefinitionValidator.java

@@ -469,27 +469,26 @@ public class StructureDefinitionValidator extends BaseValidator {
       }
       // if we see fixed[x] or pattern[x] applied to a repeating element, we'll give the user a hint
     }
-    if (snapshot) { // we just don't have enough information to figure out the context in a differential
     List<Element> constraints = element.getChildrenByName("constraint");
     int cc = 0;
     for (Element invariant : constraints) {
-        ok = validateElementDefinitionInvariant(errors, invariant, stack.push(invariant, cc, null, null), invariantMap, elements, element, element.getNamedChildValue("path"), rootPath, profileUrl) && ok;
+      ok = validateElementDefinitionInvariant(errors, invariant, stack.push(invariant, cc, null, null), invariantMap, elements, element, element.getNamedChildValue("path"), rootPath, profileUrl, snapshot) && ok;
       cc++;
     }    
-    }
     return ok;
   }
   
-  private boolean validateElementDefinitionInvariant(List<ValidationMessage> errors, Element invariant, NodeStack stack, Map<String, String> invariantMap, List<Element> elements, Element element, String path, String rootPath, String profileUrl) {
+  private boolean validateElementDefinitionInvariant(List<ValidationMessage> errors, Element invariant, NodeStack stack, Map<String, String> invariantMap, List<Element> elements, Element element, String path, String rootPath, String profileUrl, boolean snapshot) {
     boolean ok = true;
     String key = invariant.getNamedChildValue("key"); 
     String expression = invariant.getNamedChildValue("expression");
     String source = invariant.getNamedChildValue("source");
     if (warning(errors, "2023-06-19", IssueType.INFORMATIONAL, stack, !Utilities.noString(key), I18nConstants.ED_INVARIANT_NO_KEY)) {
       if (hint(errors, "2023-06-19", IssueType.INFORMATIONAL, stack, !Utilities.noString(expression) || VersionUtilities.isR5Plus(context.getVersion()), I18nConstants.ED_INVARIANT_NO_EXPRESSION, key)) { // not for R5 - there's an invariant
+        if (snapshot) {// we just don't have enough information to figure out the context in a differential
           if (!Utilities.noString(expression)) {
             if (invariantMap.containsKey(key)) {
-            // it's legal - and common - for a list of elemnts to contain the same invariant more than once, but it's not valid if it's not always the same 
+              // it's legal - and common - for a list of elements to contain the same invariant more than once, but it's not valid if it's not always the same 
               ok = rule(errors, "2023-06-19", IssueType.INVALID, stack, expression.equals(invariantMap.get(key)) || "ele-1".equals(key), I18nConstants.ED_INVARIANT_EXPRESSION_CONFLICT, key, expression, invariantMap.get(key));
             } else {
               invariantMap.put(key, expression);
@@ -512,7 +511,11 @@ public class StructureDefinitionValidator extends BaseValidator {
                   // we got to the root before finding anything typed
                   types.add(elements.get(0).getNamedChildValue("path"));
                 }
-              fpe.checkOnTypes(invariant, rootPath, types, fpe.parse(exp));
+                List<String> warnings = new ArrayList<>();
+                fpe.checkOnTypes(invariant, rootPath, types, fpe.parse(exp), warnings);
+                for (String s : warnings) {
+                  warning(errors, "2023-07-27", IssueType.BUSINESSRULE, stack, false, key+": "+s);
+                }
               } catch (Exception e) {
                 if (debug) {
                   e.printStackTrace();
@@ -521,6 +524,9 @@ public class StructureDefinitionValidator extends BaseValidator {
               }         
             }        
           }
+        } else {          
+          ok = rule(errors, "2023-07-27", IssueType.INVALID, stack, source == null || source.equals(profileUrl), I18nConstants.ED_INVARIANT_DIFF_NO_SOURCE, key, source);
+        }
       }
     }
     return ok;
@@ -552,6 +558,9 @@ public class StructureDefinitionValidator extends BaseValidator {
     } else {
       for (Element tr : element.getChildrenByName("type")) {
         String t = tr.getNamedChildValue("code");
+        if (t.startsWith("http://hl7.org/fhirpath")) {
+          t = tr.getExtensionValue("http://hl7.org/fhir/StructureDefinition/structuredefinition-fhir-type").primitiveValue();
+        }
         if (t != null) {
           if (isAbstractType(t) && hasChildren(element, elements) ) {
             types.add(element.getNamedChildValue("path"));