in reply to Re: insert element into an array
in thread insert element into an array

I obviously have a lot to learn about about the wonders of splice with arrays.
If using your example I wanted to delete the row instead of insert a new element, how would I do it ?
I tried 
 for my $rc (@R) {
  if ($rc->[0] eq "a") {
    splice @$rc, 0, 2;
  }
}

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but this just removes everything (including the line I want to delete) up to the end of the array
I also tried this 
for my $rc (@R) {
  if ($rc->[0] eq "a") {
    delete $rc->[0-2];
  }
}

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This works but then when I try to print the array out I get an uninitialized value in concatenation error.
I'd expected this because the array wasn't scrunched up and delete is not the right thing to use I guess. The print I used was
foreach (@records) {
              $buf .= "$_->[0] $_->[1] $_->[2] $_->[3]\n";
              print $buf;
}

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Re^3: insert element into an array
by davorg (Chancellor) on Nov 18, 2004 at 15:24 UTC

    Once again you're splicing the wrong array :) If you want to remove a row, then you want to alter the outer array, @R.

    But in this case, splice is really the wrong tool. Here you probably want to use grep.

    #!/usr/bin/perl

use strict;
use warnings;

use Data::Dumper;

my @R = ([qw(x y z)], [qw(a b c)], [qw(e f g)], [qw(h i j)]);

print Dumper \@R;

@R = grep { $_->[0] ne 'a' } @R;

print Dumper \@R;

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    --
    <http://www.dave.org.uk>

    "The first rule of Perl club is you do not talk about Perl club."
    -- Chip Salzenberg

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[d/l]
      Many thanks for your reply
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