title: React + Material-UI + Typescript: Inherit props from button to add different variants
body: <p>I would like to extend the default Material-UI button to add more variants such as "square."</p>
  
  <p>How can I define the prop interface to inherit/combine props.</p>
  
  <p>Here's my code:</p>
  
  <pre><code>import React from "react";
  import { Button as MuiButton } from "@material-ui/core";
  import { ButtonProps as MuiButtonProps } from "@material-ui/core/Button";
  
  interface ButtonProps extends MuiButtonProps {
    variant?: "square";
  }
  
  const defaultProps = {};
  
  const Button: React.FC&lt;ButtonProps&gt; = ({variant, children, ...props}) =&gt; {
    return (
      &lt;MuiButton variant={variant} {...props}&gt;
         {props.children}
      &lt;/MuiButton&gt;;
    )
  };
  
  Button.defaultProps = defaultProps;
  
  export default Button;
  </code></pre>
  
  <p>Ideally, I would like to use this component like so:</p>
  
  <pre><code>&lt;ExtendedButton href="/" variant="square"&gt;Click Me!&lt;/ExtendedButton&gt;
  </code></pre>