in reply to Re: small steps toward Perl literacy, temp vars and parentheses
in thread small steps toward Perl literacy, temp vars and parentheses

Hmm, your solution for keeping the lowest 2 or more elements still puts the indexing at the end, but it changes the op structure to  %h = op4 (op2 op1 %h) op3 which from a jumping back and forth from beginning to end issue is worse. But it does change the structure in another way that suggests: 
%h = map { $_, $h{ $_ } }
         shift sort { $a <==> $b } keys %h;

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(that, by the way, is completely untested. Hmm, testing says it doesn't work, type of arg 1 of shift must be array, not sort. i wasn't aware that sort was a type. I wonder how to do what I want...)

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Re^3: small steps toward Perl literacy, temp vars and parentheses
by BrowserUk (Patriarch) on Jun 17, 2004 at 00:40 UTC

    I guess we read the code in different ways. I don't think of the code as a list of operations applied to %h, but as assigning the results of map to %h.

    map takes a list and manipulates it. The fact that the input to map is also derived from %h is effectively moot. It could equally well be a completely different hash.

    I look at 

    %h = map{
    $_, $h{ $_ }
} ( sort{ $a <=> $b } keys %h )[ 0 .. 2 ];

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    as: Take the first 3 from a list of sorted keys and feed them to map. Map those keys to key/value pairs and assign them to %h.

    Examine what is said, not who speaks.
    "Efficiency is intelligent laziness." -David Dunham
    "Think for yourself!" - Abigail
    "Memory, processor, disk in that order on the hardware side. Algorithm, algoritm, algorithm on the code side." - tachyon
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