title: how to use typescript Compiler API to get normal function info, eg: returnType/parameters?
body: <pre><code>/**
   * class of User
   */
  class User {
      /**
       * constructor
       * @param name c-name
       */
      constructor(name: string) {
          this.name = name
      }
      /**
       * property name
       */
      private name: string
      /**
       * setName
       * @param name f-name
       */
      public setName(name: string) {
          this.name = name
      }
  }
  </code></pre>
  
  <p>I saw the <a href="https://github.com/Microsoft/TypeScript/wiki/Using-the-Compiler-API" rel="noreferrer">Typescript Wiki</a> and I can get the constructor's info, eg: returnType/parameters.</p>
  
  <pre><code>[
      {
          "name": "User",
          "documentation": "class of User",
          "type": "typeof User",
          "constructors": [
              {
                  "parameters": [
                      {
                          "name": "name",
                          "documentation": "c-name",
                          "type": "string"
                      }
                  ],
                  "returnType": "User",
                  "documentation": "constructor"
              }
          ]
      }
  ]
  </code></pre>
  
  <p>but i want t get the infomation of returnType/parameters/documentation on normal function <strong>getName</strong> , how can i do this? </p>
  
  <p>ps:I know the constructor has the signatures, signatures has a function <strong>getReturntype</strong>, but the normal functions has no signatures, so i can not get the info</p>
  
  <p><strong>thanks!</strong></p>