in reply to Re^5: reg. expr. multiple substitutions
in thread reg. expr. multiple substitutions

whatever escapaing might be required had you not used qr//, would still be required
Not completely. First off, if a regex $r is used as the *only* part of a pattern in /$r/ or s/$r/../, then it is not interpolated, but used as is. Secondly, by using a regex literal rather than a string literal, you get backslashed things handled right: 
$r = qr/\bfoo/; /$r/; # matches word boundary
$r = "\bfoo";   /$r/; # matches backspace

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(Although this is mostly moot, since as was pointed out elsewhere, hash keys are stored as strings.)

Dave.

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Re^7: reg. expr. multiple substitutions
by BrowserUk (Patriarch) on May 17, 2012 at 16:06 UTC
    if a regex $r is used as the *only* part of a pattern in /$r/ or s/$r/../, then it is not interpolated, but used as is.

    That's information that I've never seen written down before. Thank you.

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    The start of some sanity?
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