"ref" is referred to as if it is an already taught concept

[githubshrek]

On the Quick Start, Forms page:
https://reactjs.org/docs/forms.html
there is the sentence:
"The following example shows how a ref can be used to access file(s) in a submit handler"

There is no explanation at all of what a ref is. It's assumed that the reader knows what is being talked about.

When I was trying to understand the example, I assumed to begin with that "ref" was simply some HTML attribute with which I was not familiar.

It appears, however, that refs are a whole new, and rather complex side issue which need their own detailed explanation:
https://reactjs.org/docs/refs-and-the-dom.html

When I was trying to reproduce the example (by erasing the original and just writing it myself), the following is what I came up with. It doesn't use a ref at all, but gives the name with the path.

class FileForm extends React.Component {
  constructor(props) {
    super(props);
    
    this.handleSubmit = this.handleSubmit.bind(this);
    this.handleChange = this.handleChange.bind(this);
  }
  
  handleChange(event) {
    this.setState({value: event.target.value});
  }
  
  handleSubmit(event) {
    event.preventDefault();
    alert("File name is: " + this.state.value);
  }
  
  render() {
    return(
      <form onSubmit={this.handleSubmit} >
        <label>
          OK, pick a file, any file:
        <input type="file" onChange={this.handleChange} />
        </label>
        <br />
        <input type="submit" value="Submit" />
      </form>
    );
  }
}

ReactDOM.render(
  <FileForm />,
  document.getElementById("root")
);

I'm not sure that the example with the ref is needed in the Quick Start section on forms. Wouldn't it be better as a part of the "Refs and the DOM" page?

[gaearon]

Oops. That is definitely unintentional. I think somebody wanted to add a doc for the input file type (this section didn't exist in the beginning) but forgot about the sequencing.

This initially happened in #323. We need to think about where to move this or how to restructure.

[gaearon]

#588