The standard way is to do this is like the following: 

$ perl -Mstrict -Mwarnings -E '
> my $x = q{X-X!X?X};
> $x =~ s/([[:^upper:]])/unpack q{H2}, $1/eg;
> say $x;
> '
X2dX21X3fX

[download]

Note: I used upper instead of ascii for my example code.

There may be modules that also supply this functionality. If there are, I'm sure other monks will provide details.

-- Ken

In reply to Re: hex in regexp by kcott
in thread hex in regexp by shamanoff

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