docs(template-syntax): clarify context discussions

closes #996

Author: kwalrath

public/docs/ts/latest/guide/template-syntax.jade

@@ -6,9 +6,7 @@ include ../_util-fns
 
   Many of us are familiar with the component/template duality from our experience with model-view-controller (MVC) or model-view-viewmodel (MVVM). In Angular,  the component plays the part of the controller/viewmodel, and the template represents the view.
 
-  Let’s find out what it takes to write a template for our view. We’ll cover these basic elements of template syntax.
-
-  # Table Of Contents
+  Let’s find out what it takes to write a template for our view. We’ll cover these basic elements of template syntax:
 
   * [HTML](#html)
   * [Interpolation](#interpolation)
@@ -30,13 +28,13 @@ include ../_util-fns
   * [Input and output properties](#inputs-outputs)
   * [Template expression operators](#expression-operators)
     * [pipe](#pipe)
-    * ["elvis" (?.)](#elvis)  
+    * ["elvis" (?.)](#elvis)
 // #enddocregion intro
 .l-sub-section
   :marked
-    The [live example](/resources/live-examples/template-syntax/ts/plnkr.html) 
+    The [live example](/resources/live-examples/template-syntax/ts/plnkr.html)
     demonstrates all of the syntax and code snippets described in this chapter.
-  
+
 // #docregion html-1
 .l-main-section
 :marked
@@ -130,13 +128,13 @@ include ../_util-fns
 // #enddocregion template-expressions-2
 
 // #docregion template-expressions-context
+- var lang = current.path[1]
+- var details = lang === 'dart' ? 'template expressions can’t refer to static properties, nor to top-level variables or functions, such as <code>window</code> or <code>document</code> from <code>dart:html</code>. They can’t directly call <code>print</code> or functions imported from <code>dart:math</code>. They are restricted to referencing members of the expression context.' : 'template expressions cannot refer to anything in the global namespace. They can’t refer to <code>window</code> or <code>document</code>. They can’t call <code>console.log</code> or <code>Math.max</code>. They are restricted to referencing members of the expression context.'
 :marked
   <a id="expression-context"></a>
   ### Expression context
 
-  Perhaps more surprising, template expressions cannot refer to anything in the global namespace.
-  They can’t refer to `window` or `document`. They can’t call `console.log` or `Math.max`.
-  They are restricted to referencing members of the expression context.
+  Perhaps more surprising, !{details}
 
   The *expression context* is typically the **component instance**, which is
   the source of binding values.
@@ -241,14 +239,14 @@ include ../_util-fns
 // #enddocregion template-statements-2
 
 // #docregion template-statements-3
+- var lang = current.path[1]
+- var details = lang === 'dart' ? 'Template statements can’t refer to static properties on the class, nor to top-level variables or functions, such as <code>window</code> or <code>document</code> from <code>dart:html</code>. They can’t directly call <code>print</code> or functions imported from <code>dart:math</code>.' : 'Template statements cannot refer to anything in the global namespace. They can’t refer to <code>window</code> or <code>document</code>. They can’t call <code>console.log</code> or <code>Math.max</code>.'
 :marked
   ### Statement context
 
-  As with expressions, statements cannot refer to anything in the global namespace.
-  They can’t refer to `window` or `document`. They can’t call `console.log` or `Math.max`.
-
-  Statements are restricted to referencing members of the statement context.
-  The statement context is typically the **component instance** to which we are binding an event.
+  As with expressions, statements can refer only to what's in the statement context — typically the
+  **component instance** to which we're binding the event.
+  !{details}
 
   The *onSave* in `(click)="onSave()"` is sure to be a method of the data-bound component instance.