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docs: add template ref var to glossary (#36743) 

There is not an entry in the glossary for template
reference variable. To clarify for site visitors,
we are adding one here.

PR Close #36743
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Kapunahele Wong 2020-06-09 14:33:02 -04:00 committed by Misko Hevery
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13
aio/content/guide/glossary.md
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@ -939,6 +939,19 @@ A TypeScript-like syntax that Angular evaluates within a [data binding](#data-bi
Read about how to write template expressions in the [template expressions](guide/interpolation#template-expressions) section of the [Interpolation](guide/interpolation) guide.
{@a template-reference-variable}
## template reference variable
A variable defined in a template that references an instance associated with an element, such as a directive instance, component instance, template as in `TemplateRef`, or DOM element.
After declaring a template reference variable on an element in a template,
you can access values from that variable elsewhere within the same template.
The following example defines a template reference variable named `#phone`.
<code-example path="template-reference-variables/src/app/app.component.html" region="ref-var" header="src/app/app.component.html"></code-example>
For more information, see the [Template reference variable](guide/template-reference-variables) guide.
{@a token}
## token

7
aio/content/guide/template-reference-variables.md
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@ -19,6 +19,13 @@ Here, a `<button>` further down the template refers to the `phone` variable.
<code-example path="template-reference-variables/src/app/app.component.html" region="ref-phone" header="src/app/app.component.html"></code-example>
Angular assigns each template reference variable a value based on where you declare the variable:
* If you declare the variable on a component, the variable refers to the component instance.
* If you declare the variable on a standard HTML tag, the variable refers to the element.
* If you declare the variable on an `<ng-template>` element, the variable refers to a `TemplateRef` instance, which represents the template.
* If the variable specifies a name on the right-hand side, such as `#var="ngModel"`, the variable refers to the directive or component on the element with a matching `exportAs` name.
<h3 class="no-toc">How a reference variable gets its value</h3>
In most cases, Angular sets the reference variable's value to the element on which it is declared.