If '\\n' (3 chars) is supposed to map to a single newline, what did you want '\n' to map to? '\n' (2 chars) or 'n'?

A hash isn't necessary if you use y///. I also wouldn't worry about the e modifier in this case. You are doing nothing more in the second half of substitution than what you would have to do anyway with an arbitrary string to untaint it: testing if it is defined and eliminating and substituting characters. These examples work with all one character backslash sequences (\t\n\r\f\b\a\e), not just newlines.

For '\n' to '\n' (2 chars):

  s /\\([^\\tnrfbae])|\\\\([tnrfbae])
    /(my$x=defined($1)?$1:$2)=~y#tnrfbae#\t\n\r\f\b\a\e#;$x;
    /gex;

[download]

For '\n' to 'n', this regex would do it:

  s /\\([^\\tnrfbae])|\\\\([tnrfbae])|\\([tnrfbae])
    /(my$x=defined($1)?$1:$2?$2:'')=~y#tnrfbae#\t\n\r\f\b\a\e#;$x?$x:$
+3;
    /gex;

[download]

In reply to Re: Regexes and backslashes by ELISHEVA
in thread Regexes and backslashes by oko1

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