Re^2: Regexp works with some elements and doesn't with others

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Re^3: Regexp works with some elements and doesn't with others by diotalevi (Canon) on Feb 07, 2006 at 02:03 UTC
Use an index explicitly instead of the easily broken, implicit one you've coded. It's important to iterate in reverse so your index will still make sense after removing data. That you have these two arrays where elements exist in pairs indicates that your data structure is mismatched. This would be better served by having an array of pairs. `foreach my $ix ( reverse 0 .. $#text ) { if ( not length $text[ $ix ] ) { splice @text, $ix, 1; splice @links, $ix, 1; } }` [download] The previous is optimal on very recent perls and less so on anything older. This is a great reason to use a three-arg for loop. `for ( my $ix = $#text; $ix >= 0; -- $ix ) { # same loop contents. }` [download] ⠤⠤ ⠙⠊⠕⠞⠁⠇⠑⠧⠊	[reply] [d/l] [select]
Re^4: Regexp works with some elements and doesn't with others by lampros21_7 (Scribe) on Feb 07, 2006 at 02:06 UTC
Sorry, thats my fault. I put the wrong loop from my file. I have updated it in my previous post now.	[reply]
Re^5: Regexp works with some elements and doesn't with others by diotalevi (Canon) on Feb 07, 2006 at 02:10 UTC
`$value` is still a terrible name for an index. It's also terrible to code the plumbing of loop indexes manually when you have better alternatives available. That's why the reverse(0 .. $#array) is the preferred syntax. ⠤⠤ ⠙⠊⠕⠞⠁⠇⠑⠧⠊	[reply] [d/l]
Re^3: Regexp works with some elements and doesn't with others by bowei_99 (Friar) on Feb 07, 2006 at 02:23 UTC
Something I use sometimes is the Data::Dumper module. It helps especially with complex lists, e.g. hashes of hashes of hashes, but the same concept applies here. By using it, you can literally see how contents of variables change, or even if the original values are what you expect them to be. In this case, for example, you could modify the code to be - `use Data::Dumper; .... <snip> .... if ($text2 =~ m/^The website has been restructured/) { print "text array before is " . Dumper(\@text, $value); splice(@text,$value,1); print "text array after is " . Dumper(\@text, $value); splice(@links,$value,1); }` [download] This way, you can see for yourself how @text is changing, and how it's different from what you expect. Note that you have to pass a reference to a list to the Dumper function call, since @text is one of two elements in the list of things you want to show. Although you have to go through and uncomment/delete the Dumper lines once you've got it working, if you like actually 'seeing' changes as they happen, this may work very well for you, especially once you start using complex data structures.	[reply] [d/l]
Re^4: Regexp works with some elements and doesn't with others by diotalevi (Canon) on Feb 07, 2006 at 04:15 UTC
Hey, try this. The output is updated in place and whatever changed is highlighted as it changes. `use Data::Dumper; use Term::HiliteDiff 'watch'; for ( ... ) { my $before = "text array before is " . Dumper(\@text, $value); ... watch( $before . "text array after is " . Dumper(\@text, $value) ) +; }` [download] ⠤⠤ ⠙⠊⠕⠞⠁⠇⠑⠧⠊	[reply] [d/l]
Re^4: Regexp works with some elements and doesn't with others by GrandFather (Saint) on Feb 07, 2006 at 03:29 UTC
Even better is to use the debugger, and better still is to use an IDE such as Komodo and inspect the variables at run time without having to change your code at all. DWIM is Perl's answer to Gödel	[reply]
Re^3: Regexp works with some elements and doesn't with others by mickeyn (Priest) on Feb 07, 2006 at 10:54 UTC
Well ... wrong assumption! you can do it with 'grep' with the help of 'map': `my @tmp = grep { $_->[0] !~ /^The website has been restructured/ } map + { [$text[$_], $arr2[$_], $_] } ( 1 .. $#text ); my @text = map { $_->[0] } @tmp; my @arr2 = map { $_->[1] } @tmp; undef @tmp;` [download] note - this way you create temporary structures (map & grep), so I wouldn't use it on large arrays, but since you wrote it's a 50 elements array ... I guess you can consider this sollution. Enjoy, Mickey	[reply] [d/l]