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!';
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Yes, that was stupid of me. Thank you for pointing out my error.

Part of it is that I always use m{ ... } rather than / ... / so I have lost the habit of escaping slashes. The other part is I didn't realise that there was interpolation inside a character class so, as you point out, I failed to escape the $. Ought to do the @ as well, I suppose. Not sure about the &?

$ perl -le '
> use strict; use warnings;
> print q{whatever} =~ m{[\$&<>\@/]} ? q{Yep} : q{Nope};'
Nope
$ perl -le '
> use strict; use warnings;
> print q{v$table} =~ m{[\$&<>\@/]} ? q{Yep} : q{Nope};'
Yep
$ perl -le '
> use strict; use warnings;
> print q{bill@bloggs.com} =~ m{[\$&<>\@/]} ? q{Yep} : q{Nope};'
Yep
$
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Cheers,

JohnGG

Ought to do the @ as well, I suppose. Not sure about the &?

Neither am I. We could start a long discussion here involving eg quotemeta. But I suggest that we go no further down this line, and just accept to follow Corion's excellent advice above :

...it is a much saner approach to only allow what is permitted instead of rejecting what you know is bad.