title: Jasmine toThrow() syntax
body: <p>I have an activity I am doing for an apprenticeship opportunity and the main engineer that I could discuss this with is not responding so I figure I ask on here.
  Basically this is a 'triangle' exercise with the main purpose of writing in TDD with jasmine.</p>
  
  <p>Now, I have written the simple ones and when I moved to writing the edge cases, I am having trouble with throwing invalid input. Looking at the Docs it seems simple but my test fails with <code>invalid thrown</code> as error</p>
  
  <pre><code>describe('Triangle', function(){
  var Triangle = function(x, y, z){
    if (x &lt;= 0 || y &lt;= 0 || z &lt;= 0) {
      throw 'invalid';}
    if(x === y &amp;&amp; y === z){
      return 'equilateral';}
    if(x === y || x === z || y === z){
    return 'isosceles';}
    else{return 'scalene';}    
  };
  
    it('test triangles with no size are illegal', function() {
      var triangle = Triangle(0,0,0);
      expect(triangle).toThrow();
    });
  
  });
  </code></pre>