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So much for abstraction if you need to understand the implementation of every function you'll every use in JavaScript.

• yourad_io 13y ago
  > understand the implementation of every function Rather: remember three things that make up the majority of Array iterators' callback functions' signatures: Element, Index, Array. Shared by: .map, .every, .forEach, .filter, and probably some that I am forgetting. The exception I think is just .reduce[Right], which by definition requires its previous return value, so you have (retVal, elem, i, arr). Quite literally, if you remember .map callback, you remember .every callback :) Javascript deserves shtick for its truly bad parts (with, arguments, ...) and some missing parts, but .map and its friends aren't it.