From perlop:

The following escape sequences are available in constructs that interpolate and in transliterations. 

...
    \033    octal char    (ESC)
    \x1b    hex char    (ESC)
    \x{263a}    wide hex char    (SMILEY)
    \c[        control char    (ESC)
    \N{name}    named Unicode character

[download]

So 
from => "\x9f",
to => "\x{178}"

[download]
may be what you want. Though it looks like you have some encoding issues to think about too.

In reply to Re: Representing "binary" character in code? by ysth
in thread Representing "binary" character in code? by robinbowes

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