It's not each , but the %{...} doing reevaluation.

each expects a hash (or array with "newer" perls).

The %{} does dereferencing of the enclosed expression, which needs to be evaluated.

There is no way to tell for %{} if and why the result should be cached.

Update

To elaborate further, each is not a loop construct like foreach

It's more like a method operating on the hash, with no clear entry point.

Think %hash->each() and you can call each anytime outside while.

Update

You may rather want to take a look at this newer (5.36 experimental) syntax:


use experimental "for_list";

foreach my ($key, $value) (%hash) {
    # iterate over the hash
    # The hash is immediately copied to a flat list before the loop
    # starts. The list contains copies of keys but aliases of values.
    # This is the same behaviour as for $var (%hash) {...}
}

[download]

Cheers Rolf
(addicted to the Perl Programming Language :)
see Wikisyntax for the Monastery

In reply to Re: Why does each() always re-evaluate its argument? (Updated x2 - experimental "for_list" ) by LanX
in thread Why does each() always re-evaluate its argument? by Darkwing

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