Greetings, monks.

Let's say I have:

my %foo = map( $_ => 2*$_, 1..10 );
use Data::Dumper;
print Dumper(\%foo);

[download]

... and I (naively) expect output like:

$VAR1 = {
          '6' => 12,
          '3' => 6,
          '7' => 14,
          '9' => 18,
          '2' => 4,
          '8' => 16,
          '1' => 2,
          '4' => 8,
          '10' => 20,
          '5' => 10
        };

[download]

But that's not the result. It looks like it's being parsed as:

my %foo = map( $_, 2 * $_, 1..10 )

... where all but the first argument are flattened into a single list.

Why doesn't Perl DWIM here? In general terms, what's an EXPR and what's not (and why can't $_ => 2*$_ be one)?

Cheers,

Life is denied by lack of attention,
whether it be to cleaning windows
or trying to write a masterpiece...
-- Nadia Boulanger

In reply to map EXPR - what's an EXPR? by missingthepoint

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