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Use painless as language for painless snippets (#20185)

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The syntax highlighter does a decent job when you do this. This lets
us `grep` for painless snippets in the docs.

Closes #20025
This commit is contained in:
Nik Everett 2016-08-26 15:39:44 -04:00 committed by GitHub
parent 4ab1093564
commit 52f23918c2
1 changed files with 13 additions and 13 deletions
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26
docs/reference/modules/scripting/painless-syntax.asciidoc
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@ -15,7 +15,7 @@ including array types, but adds some additional built-in types.
==== Def
The dynamic type `def` serves as a placeholder for any other type. It adopts the behavior
of whatever runtime type it represents.
of whatever runtime type it represents.
[float]
[[painless-strings]]
@ -23,7 +23,7 @@ of whatever runtime type it represents.
String constants can be declared with single quotes, to avoid escaping horrors with JSON:
[source,js]
[source,painless]
---------------------------------------------------------
def mystring = 'foo';
---------------------------------------------------------
@ -34,14 +34,14 @@ def mystring = 'foo';
Lists can be created explicitly (e.g. `new ArrayList()`) or initialized similar to Groovy:
[source,js]
[source,painless]
---------------------------------------------------------
def list = [1,2,3];
---------------------------------------------------------
Lists can also be accessed similar to arrays: they support subscript and `.length`:
[source,js]
[source,painless]
---------------------------------------------------------
def list = [1,2,3];
return list[0]
@ -53,14 +53,14 @@ return list[0]
Maps can be created explicitly (e.g. `new HashMap()`) or initialized similar to Groovy:
[source,js]
[source,painless]
---------------------------------------------------------
def person = ['name': 'Joe', 'age': 63];
---------------------------------------------------------
Map keys can also be accessed as properties.
[source,js]
[source,painless]
---------------------------------------------------------
def person = ['name': 'Joe', 'age': 63];
person.retired = true;
@ -69,7 +69,7 @@ return person.name
Map keys can also be accessed via subscript (for keys containing special characters):
[source,js]
[source,painless]
---------------------------------------------------------
return map['something-absurd!']
---------------------------------------------------------
@ -80,13 +80,13 @@ return map['something-absurd!']
Regular expression constants are directly supported:
[source,js]
[source,painless]
---------------------------------------------------------
Pattern p = /[aeiou]/
---------------------------------------------------------
Patterns can only be created via this mechanism. This ensures fast performance, regular expressions
are always constants and compiled efficiently a single time.
are always constants and compiled efficiently a single time.
[float]
[[modules-scripting-painless-regex-flags]]
@ -116,7 +116,7 @@ using these characters:
=== Operators
All of Java's https://docs.oracle.com/javase/tutorial/java/nutsandbolts/operators.html[operators] are
supported with the same precedence, promotion, and semantics.
supported with the same precedence, promotion, and semantics.
There are only a few minor differences and add-ons:
@ -134,7 +134,7 @@ of the `switch` statement.
In addition to Java's `enhanced for` loop, the `for in` syntax from groovy can also be used:
[source,js]
[source,painless]
---------------------------------------------------------
for (item : list) {
...
@ -147,7 +147,7 @@ for (item : list) {
Functions can be declared at the beginning of the script, for example:
[source,js]
[source,painless]
---------------------------------------------------------
boolean isNegative(def x) { x < 0 }
...
@ -161,7 +161,7 @@ if (isNegative(someVar)) {
=== Lambda expressions
Lambda expressions and method references work the same as https://docs.oracle.com/javase/tutorial/java/javaOO/lambdaexpressions.html[Java's].
[source,js]
[source,painless]
---------------------------------------------------------
list.removeIf(item -> item == 2);
list.removeIf((int item) -> item == 2);