Well.... 
my @arr1;
@arr1 = map { push @arr1, ($_+ 2) } @data;

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is not the way to use map to generate a new list of @data with values of +2. here is the right way... 
my @dataPlus2 = map { my $bullshit = 'XYZ'; #see below
                      $_ + 2
                    }@data;

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map{} returns the value of the last statement. I put this $bullshit statement in there to "throw you off"...it means absolutely nothing!

Use the power of the language.

my @dataPlus2 = map { $_ + 2 }@data;
my @roots = map { sqrt($_) }@data;

map{} is best used for a line or two translations.

I wouldn't normally do it this way, this is just to show you that it is possible:

foreach my $root (map { sqrt($_) }@data)
{
   #do something with this square root...
}

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In reply to Re^3: Map Vs Foreach by Marshall
in thread Map Vs Foreach by perlCrazy

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