Re: adding elements to already exisiting elements in an array

Hello,

In addition to samtregar's comments below, if you know that you will have multiple entries, then you need to initialize the array as an array reference to begin with... for example,

Note: code has not been tested.

if ( ref( $Elements[$1] ) eq "ARRAY" ) {
   push ( @{$Elements[$l]} }, $value );
}
else {
  $Elements[$1] = [$value];
}
[download]

See perldoc -f ref for some details...

Hope this helps!

regexes

-------------------------
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-- Calvin Coolidge, 30th President of the USA.

Comment on Re: adding elements to already exisiting elements in an array Download Code

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Re^2: adding elements to already exisiting elements in an array by johngg (Canon) on May 15, 2008 at 10:17 UTC
`if ( ref( $Elements[$1] ) eq "ARRAY" ) { push ( @{$Elements[$l]} }, $value ); } else { $Elements[$1] = [$value]; }` [download] Note that you do not need to test whether you already have an array ref. as Perl will auto-vivify an anonymous array for you. `$ perl -MData::Dumper -e' > @arr = (1, 2); > push @{ $arr[2] }, 3, 4; > push @arr, 5; > print Data::Dumper->Dump([\ @arr], [q{arr}]);' @arr = ( 1, 2, [ 3, 4 ], 5 ); $` [download] Note also that samtregar's comments are above* yours, you may have your monitor upside down :-) Cheers, JohnGG	[reply] [d/l] [select]

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Re^2: adding elements to already exisiting elements in an array
by johngg (Canon) on May 15, 2008 at 10:17 UTC

if ( ref( $Elements[$1] ) eq "ARRAY" ) { push ( @{$Elements[$l]} }, $value ); } else { $Elements[$1] = [$value]; }
[download]

Note that you do not need to test whether you already have an array ref. as Perl will auto-vivify an anonymous array for you.

$ perl -MData::Dumper -e'
> @arr = (1, 2);
> push @{ $arr[2] }, 3, 4;
> push @arr, 5;
> print Data::Dumper->Dump([\ @arr], [q{*arr}]);'
@arr = (
         1,
         2,
         [
           3,
           4
         ],
         5
       );
$
[download]

Note also that samtregar's comments are above yours, you may have your monitor upside down :-)

Cheers,

JohnGG

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