in reply to Re: iterating 2 arrays in parallel
in thread iterating 2 arrays in parallel

pairwise from List::MoreUtils requires that both arrays have the same length, you can get the same behaviour easily without using any extra module at all:

my @combined = map {"$a1[$_]:$a2[$_]"} ($#a1 < $#a2 ? (0..$#a2) : (0..
+$#a1));

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This version can be easily fixed to treat arrays of different length:

my @combined = map {($a1[$_]//"").":".($a2[$_]//"")} ($#a1 < $#a2 ? (0
+..$#a2) : (0..$#a1));

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citromatik

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Re^3: iterating 2 arrays in parallel
by linuxer (Curate) on Apr 15, 2009 at 10:37 UTC

    The given example uses arrays of the same length, so pairwise looks fine to me.

    And if they are not of the same length, I think the same way as JavaFan, that iswas left as an exercise to the reader. I don'tdidn't want to guess, what has to happen if the lengths differ. It's the OP who should know, what to do.

    Nevertheless, thanks for your examples ;o)

    Update:

    What about this pairwise solution to work with arrays of different lengths: 

    use List::MoreUtils qw( pairwise );
my @a=(1 .. 5 );
my @b=( 'a' .. 'c'  );

### Good point from JavaFan; bad idea to ignore 0
### my @combined = pairwise { ( $a || '' ) .':'. ( $b || '' ) } @a, @b
+;

### fixed:
my @combined = pairwise { ( defined $a ? $a : '' ) .':'. ( defined $b 
+? $b : '' ) } @a, @b;

{
  local $,="\n",
  print @combined;
}

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      I think it's a bad idea to replace a 0 with an empty string as your solution does. Either use defined, '//', or just turn off warnings.
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        Damn, right. I feared I missed something ;o). Fixed code and used defined(). Thank you.

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