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JavaScript The Module Pattern in JavaScript

Jonathan Kuhl
Jonathan Kuhl
26,133 Points
Posted by Jonathan Kuhl
Jonathan Kuhl
26,133 Points

"Uncaught SyntaxError: Identifier 'exports' has already been declared"

I'm trying to set up my own module, just a basic library that makes it easier to use typical canvas functions. When I try to make my model like the one in the video, I keep getting this error, and it keeps claiming that the model name that I pass in is "not defined."

Here's the code:

let EasyCanvas = (function(exports) {

    "use strict";

    const exports = {
         //.....contents
     }

return exports;
})(EasyCanvas || {});

What am I missing?

1 Answer

Steven Parker
Steven Parker
231,269 Points
Steven Parker
Steven Parker
231,269 Points

The identifier "exports" is already in use as the name of your passed-in argument. So with "strict" mode on, when you create a new constant with that same name, you get the "already in use" error.