What does the error “JSX element type '…' does not have any construct or call signatures” mean?

Question

I wrote some code:

function renderGreeting(Elem: React.Component) {
    return Hello, !;
}


        

Answer 1

When I'm converting from JSX to TSX and we keep some libraries as js/jsx and convert others to ts/tsx I almost always forget to change the js/jsx import statements in the TSX\TS files from

import * as ComponentName from "ComponentName";

to

import ComponentName from "ComponentName";

If calling an old JSX (React.createClass) style component from TSX, then use

var ComponentName = require("ComponentName")