Added a jsdoc example for withContext()

Fixes jasmine/jasmine.github.io#166

lib/jasmine-core/jasmine.js

@@ -3667,19 +3667,24 @@ getJasmineRequireObj().Expectation = function(j$) {
   }
 
   /**
-   * Add some context for an {@link expect}
+   * Add some context to be included in matcher failures for an
+   * {@link expect|expectation}, so that it can be more easily distinguished
+   * from similar expectations.
    * @function
    * @name matchers#withContext
    * @since 3.3.0
    * @param {String} message - Additional context to show when the matcher fails
    * @return {matchers}
+   * @example
+   * expect(things[0]).withContext('thing 0').toEqual('a');
+   * expect(things[1]).withContext('thing 1').toEqual('b');
    */
   Expectation.prototype.withContext = function withContext(message) {
     return addFilter(this, new ContextAddingFilter(message));
   };
 
   /**
-   * Invert the matcher following this {@link expect}
+   * Invert the matcher following this {@link expect|expectation}
    * @member
    * @name matchers#not
    * @since 1.3.0

src/core/Expectation.js

@@ -16,19 +16,24 @@ getJasmineRequireObj().Expectation = function(j$) {
   }
 
   /**
-   * Add some context for an {@link expect}
+   * Add some context to be included in matcher failures for an
+   * {@link expect|expectation}, so that it can be more easily distinguished
+   * from similar expectations.
    * @function
    * @name matchers#withContext
    * @since 3.3.0
    * @param {String} message - Additional context to show when the matcher fails
    * @return {matchers}
+   * @example
+   * expect(things[0]).withContext('thing 0').toEqual('a');
+   * expect(things[1]).withContext('thing 1').toEqual('b');
    */
   Expectation.prototype.withContext = function withContext(message) {
     return addFilter(this, new ContextAddingFilter(message));
   };
 
   /**
-   * Invert the matcher following this {@link expect}
+   * Invert the matcher following this {@link expect|expectation}
    * @member
    * @name matchers#not
    * @since 1.3.0