perl switch case

Below shows how to emulate the switch... case ... construct in C

 

 

# file:
#   switch_emu.pl
# description:
#   this is the file to show how to simulate the switch ... case ... construct in Perl
#
# conclusion:
#    perl does not have switch case...
#    You can emulate switch ... case with bare blocks and label
#
use strict;

SWITCH:
{
	if (/^abc/) { $abc =1; last SWITCH; }
	if (/^def/) { $def =1; last SWITCH; }
	if (/^xyz/) { $xyz =1; last SWITCH; }
	$nothing = 1;
}


SWITCH1:
{
	/^abc/       && do { $abc =1; last SWITCH1; }
	/^def/       && do { $def =1; last SWITCH1; }
	/^xyz/       && do { $xyz =1; last SWITCH1; }
	$nothing = 1
}

if (/^abc/)    { $abc = 1}
elsif (/^def/) { $def = 1 } 
elsif (/^def/) { $def = 1 } 
else           { $nothing = 1 }


# the last in the do { } blocks does not exit the do {} block , 
# but rather exit the for loop
for ($very_nasty_long_name[$i++][$j++]->method()) {
	/this pattern/   and do { push @flags, '-e'; last; };
	/that pattern/   and do { push @flags, '-h'; last; };
	/something else/ and do {                    last; };
	die "unknown value: '$_'";
}
 

 

 

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