requirejs源码分析: define 方法

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define = function (name, deps, callback) {
var node, context;

//Allow for anonymous modules
if (typeof name !== 'string') {
//Adjust args appropriately
callback = deps;
deps = name;
name = null;
}

//This module may not have dependencies
if (!isArray(deps)) {
callback = deps;
deps = null;
}

//If no name, and callback is a function, then figure out if it a
//CommonJS thing with dependencies.
if (!deps && isFunction(callback)) {
deps = [];
//Remove comments from the callback string,
//look for require calls, and pull them into the dependencies,
//but only if there are function args.
if (callback.length) {
callback
.toString()
.replace(commentRegExp, '')
.replace(cjsRequireRegExp, function (match, dep) {
deps.push(dep);
});

//May be a CommonJS thing even without require calls, but still
//could use exports, and module. Avoid doing exports and module
//work though if it just needs require.
//REQUIRES the function to expect the CommonJS variables in the
//order listed below.
deps = (callback.length === 1 ? ['require'] : ['require', 'exports', 'module']).concat(deps);
}
}

//If in IE 6-8 and hit an anonymous define() call, do the interactive
//work.
if (useInteractive) {
node = currentlyAddingScript || getInteractiveScript();
if (node) {
if (!name) {
name = node.getAttribute('data-requiremodule');
}
context = contexts[node.getAttribute('data-requirecontext')];
}
}

//Always save off evaluating the def call until the script onload handler.
//This allows multiple modules to be in a file without prematurely
//tracing dependencies, and allows for anonymous module support,
//where the module name is not known until the script onload event
//occurs. If no context, use the global queue, and get it processed
//in the onscript load callback.
(context ? context.defQueue : globalDefQueue).push([name, deps, callback]);
};