Your alternation \$|&|<|>|@|\/ would be better expressed as a character class [$&<>@/].

Not really, no:

use strict;
use warnings;

my $name = 'whatever';
print $name =~ /[$&<>@/]/ ? 'Yep!' : 'Nope!';

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Output:

Unmatched right square bracket at C:\Perl\progs\junk.pl line 5, at end
+ of line
syntax error at C:\Perl\progs\junk.pl line 5, near "/[$&<>@/]"
Search pattern not terminated or ternary operator parsed as search pat
+tern at junk.pl line 5.

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Drat! Let's escape that pesky slash:

my $name = 'whatever';
print $name =~ /[$&<>@\/]/ ? 'Yep!' : 'Nope!';

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Output:

Use of uninitialized value in concatenation (.) or string at junk.pl l
+ine 5.
Nope!

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What's happening now? Ah, perl seems to think that $& means $MATCH. Why can't it DWIM? Let's try this:

my $name = 'whatever';
print $name =~ /[&$<>@\/]/ ? 'Yep!' : 'Nope!';

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Aah, that's better!

Update: fixed typo, closed blockquote tag.

Update 2: just realised that there's yet another problem. The dollar sign has to be escaped as well:

my $name = 'what$ever';
print $name =~ /[\$&<>@\/]/ ? 'Yep!' : 'Nope!';

[download]

In reply to Re^2: Regex and negative file test by Not_a_Number
in thread Regex and negative file test by neilwatson

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