I'm often tempted to jump into the source code of the framework/libraries that I consume. In react, the source code lies inside the /src folder https://github.com/facebook/react/tree/master/src
To start with, the best way is to go through the modules with no or less dependencies. Usually, the utils will have less dependencies but they would be consumed a lot throughout. So, I feel its good to start with them.
React shares some utilities from https://github.com/facebook/fbjs
- invariant
- keyMirror
- keyOf
- emptyFunction
- warning
- mapObject
- camelizeStyleName
- memoizeStringOnly
- hyphenateStyleName
- ExecutionEnvironment
Once you glimsed the above, start with the general utils that lies inside the /shared folder https://github.com/facebook/react/tree/master/src/shared/utils
I'll provide insights on important modules. Many other modules will look self explanatory. (eg: isTextInputElement)
Aims at reusing the object instances. The object instances should have a destructor method to reset the instance state
var PooledClass = require('PooledClass');
// Poolable Class
function Person(options) {
this.name = options.name;
}
Person.prototype.destructor = function() {
this.name = null;
}
PooledClass.addPoolingTo(Person); // augments the Person class with PooledClass
let personInstance = Person.getPooled(); // returns an instance from the pool. If there are no instances in the pool, returns a new instanceHandles validation on the PropTypes. Each validation is chainable
Object which contains the owner component
Constains a map of supported HTML tags >> React Component classes
Handles unitless CSS properties like flex, colCount, tabSize, etc & shorthand CSS property expansion like background, font, etc
Will keep updating the gist as and when I explore the codebase