in reply to Re^12: the annoying keys "key" and "value"
in thread the annoying keys "key" and "value"

So why would someone try to represent a hash with an array of two element hashes each with the keys "key" and "value"?

"Represent a hash" makes no sense. I presume you mean "implement an associative array".

Someone would do that if they wanted to preserve the order of the tuples. We've covered this multiple times already.

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Re^14: the annoying keys "key" and "value"
by jabowery (Beadle) on Dec 24, 2010 at 06:32 UTC
    So you want to have an ordered associative array by using: [{'key'=>somekey1,'value'=>somevalue1},...] because that is superior to having: $order=[somekey1,somekey2,...]; and {somekey1=>somevalue1,...} ?

    Is this because using the associative array for its primary function -- looking up values from keys -- is so much more convenient and efficient your way?

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      It's not a question of efficiency, it's a question of actually working. $order=[somekey1,somekey2,...]; and {somekey1=>somevalue1,...} doesn't support more than one value with the same key.

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        For clarity, what you are calling an ordered associative array is actually an ordered relation. The definition of "associative array" is functional (ie: one value per key), not relational (ie: potentially N values per key). So we have: 
        <ordered_relation_foo>
<b>2</b>
<b>4</b>
<a>1</a>
<b>6</b>
<a>3</a>
<a>5</a>
</ordered_relation_foo>

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        becomes: 
        $ordered_relation_foo={
    _meta_order=>[b,b,a,b,a,a],
    b=>[2,4,6],
    a=>[1,3,5]};

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        So now a query of this ordered relation becomes: 
        $ordered_relation_foo{a}

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        How does that compare to the query of your structure?
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