tr
Performs character-by-character transliteration on a string.
Transliterates characters in the target string according to a precompiled translation table. Each character found in the search list is replaced by the corresponding character in the replacement list.
The target string is obtained from the targ pad slot, the stack,
or $_. For tr/// (OP_TRANS), the string is modified in place
and the count of translated characters is pushed. For tr///r
(OP_TRANSR), a new modified copy is pushed instead.
Modifiers (encoded in op_private):
/c(0x20): Complement the search list/d(0x80): Delete found but unreplaced characters/s(0x08): Squash duplicate replaced characters
Synopsis
$str =~ tr/searchlist/replacementlist/;
$str =~ y/a-z/A-Z/; # y is a synonym
my $count = ($s =~ tr/a//); # count occurrences
my $new = $s =~ tr/a-z/A-Z/r; # /r returns copy