lparvinsmith / js-module-inline-08 Goto Github PK

#Module Exercise

Here, we will build an inline module like the following step-by-step:

var module = (function(arg, transform) {
	// secret internals
	var value = arg;

	// exports
	return function() {
		// has access to secret internals!
		value = transform(value);

		return value;
	};
})(something);

This repository features a solved branch for future reference.

##Step 1 Once you've forked and cloned this repo, you're ready to start the exercise.

1. Open index.js.
2. Look at the code and ask questions if anything looks foreign.
3. Leave f as-is or alter it to create a more interesting module.
4. Leave the statements toward the end of the document as-is or alter them to do something more interesting.
5. Run the script with npm start or node index.js.

##Step 2

1. Open index.js.
2. Put a pair of parens (( and )) around our declaration of f.

Recall that the function declaration begins with the keyword function and ends with the closing curly brace (}) following the function body. Your opening paren belongs before the letter 'f' in function and your closing paren belongs after }.

3. Observe that this makes no actual change in what the code does. Surrounding a value with parens does nothing to change it. Run the script again if you like.

##Step 3 Since we named our function f, we know that the f being called where we define module is the same function, right? We can replace f with the actual function declaration, then, and it'll be the same, won't it?

1. Copy the declaration of f in index.js, with the parens that surround it.
2. Substitute the declaration you copied for f in the line where we declare and define the variable module.
3. Remove the declaration of f from the lines above our declaration of module.
4. Run the script again and observe any difference in the result.

##Step 4

1. Look at the code you've created to generate and store a module in module.
2. Look at the code at the top of this page.