I am on Win32, AS 5.8.7.
I am ran into a character substitution problem, any enlightment would be great. I built a pure perl Pdf module and was testing my tables with some ascii art. I have to escape every '\' with '\\' in the string I embed in the Pdf. This code does work, but only if the '\' is not followed by another '\': 
$txt = ' \*/  ';
$txt =~s/\\/\\\\/g;  # what I expected ' \\*/ ';
print $txt;

[download]
but, it does not work when there this 2 or more 
$txt = ' __\\U//__ ';
$txt =~s/\\/\\\\/g;
print $txt;
#prints __\\U//__

[download]
I needed it to do this '__\\\\U//__'
Can anyone show me how to do this?
Thanks,
JamesNC
This is kindof solved, thanks to everyone who responded.
Update: I posted a follow-up. I would still like some more info on why ikegami's suggestion of streaming the data makes a difference.
Closing note:
This is a "special helpful programming feature" of perl that backslashes are interpreted as backslashes inside of single quotes except in the case where a backslash is followed by another backslash, in which case the pair escape each other. It is documented in perlop as was pointed out to me by ambrus. All this because I started messing with ascii art.

In reply to Escaping multiple escape chars by JamesNC

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