Re^2: How to use a variable in tr///

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Re^3: How to use a variable in tr/// by merlyn (Sage) on Apr 08, 2005 at 12:43 UTC
why not just eval? Because with eval, you must worry about delimiters. For example, if either string had contained "/", the eval example given elsewhere in this thread would fail. Also, eval invites disaster in a proxy-privilege environment (like CGI or other daemons). The lookup table isn't hard to create: `## initialization my $old = 'abc'; my $new = 'xyz'; my %table; @table{split //, $old} = split //, $new; my $table_re = join '\|', map quotemeta reverse sort keys %table; ## the deed my $string = 'abracadabra'; $string =~ s/($table_re)/$table{$1}/g;` [download] -- Randal L. Schwartz, Perl hacker Be sure to read my standard disclaimer if this is a reply.	[reply] [d/l]
Re^4: How to use a variable in tr/// by Roy Johnson (Monsignor) on Apr 08, 2005 at 12:49 UTC
The "why not just eval?" referred to the case of embedding an eval'd tr/// in an s///e, which would be no better. But your cautions are valid. [Update: and addressed here] Update: Though for character replacement, I'd build the regex using a character class rather than alternation: `my $table_re = sprintf '[%s]', join '', map quotemeta, keys %table;` [download] Caution: Contents may have been coded under pressure.	[reply] [d/l]
Re^3: How to use a variable in tr/// by Hena (Friar) on Apr 08, 2005 at 11:33 UTC
Umm... right you are... Silly me :). Usually i just try to stay away from eval as it can be nasty sometimes.	[reply]


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