From: John Carter <john.carter@...>
Date: 2005-05-04T07:29:05+09:00
Subject: Re: mapping an array to a hash?

On Wed, 4 May 2005, Nick Woolley wrote:

> Can anyone suggest an idiomatic ruby equivalent to this perl snippet?
>
>  my %index = map { $_ => compute_something($_) } @files;

> The best I came up with so far seems reletively clunky to me:
>
>  index = Hash.new()
>  files.each {|f| index[f] = compute_something(f) }

If you want mind bending and obscure, try...

index = Hash.new{|hash,key| hash[key] = compute_something(key)}

and then somewhere totally elsewhen in the code...

files.each{|f| index[f]}


John Carter                             Phone : (64)(3) 358 6639
Tait Electronics                        Fax   : (64)(3) 359 4632
PO Box 1645 Christchurch                Email : john.carter@tait.co.nz
New Zealand


Somewhere on the edge of a Galaxy, one of literally billions of such
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galaxy.

Orbiting that sun is a small rock 330000 times smaller than that
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This rock is  covered by a very very thin scum  of life. (Think 6000km
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Amongst the millions of species in that scum are many hundreds of
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Surprisingly enough, this email does not originate from a beetle.

It originates from just one of the 6 billion vastly outnumbered humans.

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