If two variables match

ivanatora has asked for the wisdom of the Perl Monks concerning the following question:

Replies are listed 'Best First'.
Re: If two variables match by Corion (Patriarch) on Nov 24, 2005 at 20:24 UTC
There are many ways you could move forward from here: One way is to convert both values to a unified representation, for example all-upper-case or all-lower-case, and then compare the two with simple string equality: `if (uc $vord eq uc $nick) { ... }` [download] Another way is to compile your `$nick` into a safe regular expression and check against that: `if ($vord =~ /^\Q$nick\E$/i) { ... }` [download] The `\Q` .. `\E` escapes turn of the interpretation of all regular-expression metacharacters in-between them.	[reply] [d/l] [select]
Re^2: If two variables match by Tanktalus (Canon) on Nov 25, 2005 at 04:42 UTC
Side note on option 1. English may let you get away with uc'ing to do a comparison. Certain other languages do not. It's just a good I18N habit to get into to always use lower-case to compare. I've never really fully understood this advice from our I18N experts at work, but I take their word for it. Even if that makes me a bit of a cargo-culter. I'm not ashamed to admit it - I'm a unilingual person, so to keep from ticking off our Nordic customers, I'm more than happy to follow this advice. ;-) Also, side note on option 2 - I think that option 1 is likely to be significantly faster. Benchmark to be sure.	[reply]
Re^3: If two variables match by Corion (Patriarch) on Nov 25, 2005 at 07:49 UTC
If you want to give your language experts a counter example, in German, the "sharp-S" / "eszet" letter "ß", compounded of "s" and "z", has no uppercase equivalent and is always written as "SS" when uppercased. For example `straße` ("street") becomes `STRASSE`. If you want to match case-insensitively here, you either have to normalize all ß to "`ss`" before comparing or you can "normalize" by converting to upper case. But I admit that this is some corner case which is unlikely to affect non-Germans :-)	[reply]
Re: If two variables match by cog (Parson) on Nov 24, 2005 at 20:21 UTC
`if ( (lc $vord) eq (lc $nick) ) { ...` [download]	[reply] [d/l]
Re: If two variables match by monarch (Priest) on Nov 24, 2005 at 22:38 UTC
It appears you're watching to see if two variables contain the same data (ignoring case). However if you want to see if one variable contains the value of another variable e.g. `my $vord = "Something Very Long"; my $nick = "Very";` [download] ..then you probably don't want the anchors in your regular expression..e.g. `if ( $vord =~ m/\Q$nick\E/i ) { ... }` [download]	[reply] [d/l] [select]