I'm testing the following using Perl 5.24.0.

Observe the strange behavior of "tr" when single-quotes are used as delimiters:

Input: 

#!/usr/bin/perl -w --
$s = '-abcdefgh'; $s =~ tr/abc//cd; print "s = '$s'\n";
$s = '-abcdefgh'; $s =~ tr/a-c//cd; print "s = '$s'\n";
$s = '-abcdefgh'; $s =~ tr'abc''cd; print "s = '$s'\n";
$s = '-abcdefgh'; $s =~ tr'a-c''cd; print "s = '$s'\n";

[download]

Output: 

s = 'abc'
s = 'abc'
s = 'abc'
s = '-ac'

[download]

Effectively, character ranges get disabled when this specific character is used as the delimiter, and "-" becomes just one more literal character in the SEARCHLIST. Is this outcome intended? Did I miss where this special case is documented? I would expect an exception like that to be listed in the doc (tr leads you to Quote Like Operators; scroll down a bit to the part on tr and y).

In reply to undocumented tr special behavior for single-quoted transform by Anonymous Monk

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