All I want access to is the keys...
ok, but a hash has a key and a value. So your code should be: 
my @keys = qw{ a b c d };
my %hash = map { $_,1 } @keys;

[download]
if you want your keys unaltered. If you want a "string increment" ($_="a";$_++; # $_ is b now) its ok to use $_++.

In the loop 

my %hash;
foreach ( @keys ) {
    $hash{$_}++;
}

[download]

you are also using two variables - in a shortcut:

  1. you create a new hash slot with key $_
  2. you increment (the previously undefined) value for that key

So, it's the same thing with keys and values here. With map iterating over an array of keys, you must provide a value to have pairs to be stored as (key,value) in a hash.

--shmem 

_($_=" "x(1<<5)."?\n".q·/)Oo.  G°\        /
                              /\_¯/(q    /
----------------------------  \__(m.====·.(_("always off the crowd"))."·
");sub _{s./.($e="'Itrs `mnsgdq Gdbj O`qkdq")=~y/"-y/#-z/;$e.e && print}

In reply to Re^5: Hash assignments using map by shmem
in thread Hash assignments using map by njcodewarrior

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