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Comment by ricardobeat | Hacker News Reader

I've been using a pair of functions applyRight/Left that fit this case nicely:

     ['10','10','10','10'].map(applyRight(null, parseInt, [10], 1)

The signature is [context, fn, args, slice] where `slice` is the length of arguments to keep from invocation. It's very rare that something warrants using it vs an anonymous function though.

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That's interesting, I like how `slice` lets you concat sequences of arguments, but worry about building functions which have too many convenience features. Thought experiment: what if I wanted to pass every other argument?

I imagine you could pass a function

   function(arg, i){ return i%2 }

as the `slice` parameter, but that's going into crazy territory.

Here's what I use:

  # Adapted from http://autotelicum.github.com/Smooth-CoffeeScript/literate/partial.html
  F.partial = (func, a...) -> (b...) ->
    func (for arg in a then arg ?= b.shift())..., b...

For example, do `parseInt10 = F.partial(parseInt, undefined, 10)`, then `[].map(parseInt10)` does the right thing.

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