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Defers performing I/O for required modules until they are first used
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Deferred Require

Using this module requires that you run node with the --harmony_proxies and --harmony_collections flags.

deferredRequire = require 'deferred-require'
myHugeModule = require 'my-huge-module'

# ... some time later ...

myHugeModule.doSomething() # the module isn't loaded and required until here

This npm exports a single top-level function, deferredRequire, which you can use just as you would use node's global require function. When you require a module with deferredRequire, no code is actually loaded or evaluated until the module you require is first used. This is achieved through the magic of harmony proxies.

Warning: Because of instability in the v8 proxy implementation when combined with "exotic objects" like arrays, strings, and dates, you should only use deferredRequire with modules that export regular objects or functions as their top-level module. This is true of almost every npm module, so in practice this shouldn't be a big issue.

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