comb

comb() is a function (or method) which, in certain respects, is the mirror-image of split().

my ($str, $comb, @rv);
$str = 'This is a string to be split';
say q|$str:                     |, $str;
$comb = 'This is a string to be combed';
say q|$comb:                    |, $comb;
say '';
say "split on multiple-character delimiter -- 'tri' -- found in string:";
say q|split('tri', $str);|;
@rv = split('tri', $str); print "<$_>" for @rv; print "\n";
say '';
say "comb on multiple-character string matcher -- 'tri' -- found in string:";
say q|comb('tri', $comb);|;
@rv = comb('tri', $comb); print "<$_>" for @rv; print "\n";
say '';
say "comb on multiple-character pattern matcher -- /tri/ -- found in string:";
say q|comb(/tri/, $comb);|;
@rv = comb(/tri/, $comb); print "<$_>" for @rv; print "\n";
say '';
say "/[tri]/ produces same output as above; why?";
say q|comb(/[tri]/, $comb);|;
@rv = comb(/[tri]/, $comb); print "<$_>" for @rv; print "\n";
say '';
say "but /<[tri]>/ behaves more like a character class";
say q|comb(/<[tri]>/, $comb);|;
@rv = comb(/<[tri]>/, $comb); print "<$_>" for @rv; print "\n";
say '';
say "integer '1' as matcher for comb()";
say q|comb(1, $comb);|;
@rv = comb(1, $comb); print "<$_>" for @rv; print "\n";
say '';
say "integer '7' as matcher for comb()";
say q|comb(7, $comb);|;
@rv = comb(7, $comb); print "<$_>" for @rv; print "\n";
say '';
say "limit the number of fields returned by comb()";
say q|comb(7, $comb, 2);|;
@rv = comb(7, $comb, 2); print "<$_>" for @rv; print "\n";
say '';
say "method format";
say q|$comb.comb(7, 2);|;
@rv = $comb.comb(7, 2); print "<$_>" for @rv; print "\n";
say '';
say '';
my $ncomb = 'This is a different string to be combed triumphantly';
say q|$ncomb:                    |, $ncomb;
say '';
say "comb on multiple-character string matcher -- 'tri' -- found in string:";
say q|comb('tri', $ncomb);|;
@rv = comb('tri', $ncomb); print "<$_>" for @rv; print "\n";
say '';
say "comb on multiple-character pattern matcher -- 'tri' -- found in string:";
say q|comb(/tri/, $ncomb);|;
@rv = comb(/tri/, $ncomb); print "<$_>" for @rv; print "\n";
say '';
say "integer '1' as matcher for comb()";
say q|comb(1, $ncomb);|;
@rv = comb(1, $ncomb); print "<$_>" for @rv; print "\n";
say '';
say "integer '7' as matcher for comb()";
say q|comb(7, $ncomb);|;
@rv = comb(7, $ncomb); print "<$_>" for @rv; print "\n";
say '';
say "limit the number of fields returned by comb()";
say q|comb(7, $ncomb, 2);|;
@rv = comb(7, $ncomb, 2); print "<$_>" for @rv; print "\n";
say '';
say "method format";
say q|$ncomb.comb('tri');|;
@rv = $ncomb.comb('tri'); print "<$_>" for @rv; print "\n";

Output:

$str:                     This is a string to be split
$comb:                    This is a string to be combed

split on multiple-character delimiter -- 'tri' -- found in string:
split('tri', $str);
<This is a s><ng to be split>

comb on multiple-character string matcher -- 'tri' -- found in string:
comb('tri', $comb);
<tri>

comb on multiple-character pattern matcher -- /tri/ -- found in string:
comb(/tri/, $comb);
<tri>

/[tri]/ produces same output as above; why?
comb(/[tri]/, $comb);
<tri>

but /<[tri]>/ behaves more like a character class
comb(/<[tri]>/, $comb);
<i><i><t><r><i><t>

integer '1' as matcher for comb()
comb(1, $comb);
<T><h><i><s>< ><i><s>< ><a>< ><s><t><r><i><n><g>< ><t><o>< ><b><e>< ><c><o><m><b><e><d>

integer '7' as matcher for comb()
comb(7, $comb);
<This is>< a stri><ng to b><e combe><d>

limit the number of fields returned by comb()
comb(7, $comb, 2);
<This is>< a stri>

method format
$comb.comb(7, 2);
<This is>< a stri>

$ncomb:                    This is a different string to be combed triumphantly

comb on multiple-character string matcher -- 'tri' -- found in string:
comb('tri', $ncomb);
<tri><tri>

comb on multiple-character pattern matcher -- 'tri' -- found in string:
comb(/tri/, $ncomb);
<tri><tri>

integer '1' as matcher for comb()
comb(1, $ncomb);
<T><h><i><s>< ><i><s>< ><a>< ><d><i><f><f><e><r><e><n><t>< ><s><t><r><i><n><g>< ><t><o>< ><b><e>< ><c><o><m><b><e><d>< ><t><r><i><u><m><p><h><a><n><t><l><y>

integer '7' as matcher for comb()
comb(7, $ncomb);
<This is>< a diff><erent s><tring t><o be co><mbed tr><iumphan><tly>

limit the number of fields returned by comb()
comb(7, $ncomb, 2);
<This is>< a diff>

method format
$ncomb.comb('tri');
<tri><tri>