While understanding what map{} is supposed to do, I seem to be consistently unable to use it correctly... which suggests that, on some level I really don't know what it actually does.

As I understand it, map{} applies some function (defined within the BLOCK) to each element of an array and the result is passed to the left.

So, you could, for instance, write a for loop without using a for simply by writing:

my @array = (1, 2, 3, 4, 5);
my @adjusted_array = map { $_ * 10 } @array;
print (join ',', @adjusted_array);

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But what about more complicated statements?

I make it about as far as loading a hash from an array that I've split before it all starts to look like a monkey hitting the keys largely at random.

my @array = ('one-1', 'two-2', 'three-3', 'four-4', 'five-5');
my %hash = map { split /-/ } @array;
print (join ',', keys %hash);

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Why, for instance, could I not work this through even though it's clearly a mapping situation?

if ($access) {
    foreach (@{$access}) {
        $set{$_->[0]} = $_->[1];
    }
}

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I guess what I'm seeking is the wisdom to understand how map operates within the BLOCK since most mentions of the map{} function are either cryptic or basic and I fall somewhere in between.

TIA

In reply to Back to Remedial Perl for Me: map{} function by jreades

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