title: " 'default parameter' is not defined" in my react app
body: <p>I am going to attempt to post this without having to share my 1500 lines of code for a react component that I've built. Here is the general structure of my component, like any other:</p>
  
  <pre><code>import React, { Component } from 'react';
  import d3 from "d3";
  
  class presComponent extends Component {
  
  constructor(props) { 
      super(props);
      this.state = { ... }
  }
  
  someHelperFunction(paramA="blue", paramB="red") { ... }
  
  componentDidMount() {
      this.someHelperFunction(paramA="blue", paramB="red")
  }
  
  render() {
     ... 
  </code></pre>
  
  <p>After my constructor I have a number of functions that I used to organize my code, that are called in the lifecycle methods (DidMount and DidUpdate, for the most part). Some of my helper functions have default parameters, in this case <em>someHelperFunction</em> has parameters paramA and paramB, with default values blue and red. </p>
  
  <p>This component is a presentational component, and I call it from within one of my main container components. When I do, I receive the following errors:</p>
  
  <pre><code>Line 1735:  'paramA' is not defined       no-undef
  Line 1735:  'paramB' is not defined       no-undef
  </code></pre>
  
  <p>Line 1735 in my code is the calling of the function inside of componentDidMount, so the following line:</p>
  
  <pre><code>this.someHelperFunction(paramA="blue", paramB="red")
  </code></pre>
  
  <p>Why is this the case. Even though in my example I set the parameter values to their default values, even if I do not use the default values I receive this error. Any help here is appreciated, it feels like I don't understand the use of default parameters for a function in javascript / react. </p>
  
  <p>Thanks!</p>