#!/usr/bin/perl use strict; use warnings; # 930247 my $var = 0; if ( $var ) { print "\$var ($var) True\n"; } else { print "\$var ($var) False\n"; } undef $var; if ( $var ) { print "\$var (undef) True\n"; } else { print "\$var (undef) False\n"; } my $var1 = ''; if ( $var1 ) { print "\$var1 ('') True\n"; } else { print "\$var1 ('') False\n"; } my $var2 = ""; if ( $var2 ) { print "\$var2 (\"\") True\n"; } else { print "\$var2 (\"\") False\n"; } my $var3 = '0'; if ( $var3 ) { print "\t \$var3 ($var3 - as a single-quoted number) True\n"; } else { print "\t \$var3 ($var3 - as a single-quoted number) False\n"; } my $var4 = "0"; if ( $var4 ) { print "\t \$var4 ($var4 - as a double-quoted number) True\n"; } else { print "\t \$var4\ ($var4 - as a double-quoted number) False\n"; } if ( $var4 == 0 ) { print "\t \$var4 ($var4 - as an unquoted number) True\n"; } else { print "\t \$var4 ($var4 - as an unquoted number) False\n"; } if ( $var4 eq '0' ) { print "\t \$var4 ($var4 - as a single-quoted number) True\n"; } else { print "\t \$var4 ($var4 - as a single-quoted number) False\n"; } print "\t \$var4 ($var4 - as a single-quoted number) has length of " . length($var4) . " and ASCII value of " .ord($var4). "\n"; my $var5 = '1'; if ( $var5 ) { print "\$var5 ($var5 in single quotes) True\n"; } else { print "\$var5 ($var5 in single quotes) False\n"; } my $var6 = "1"; if ( $var6 ) { print "\$var6 ($var6 in double quotes) True\n"; } else { print "\$var6 ($var6 in double quotes) False\n"; } my $var7 = 1; if ( $var7 ) { print "\$var7 ($var7 - as an unquoted number) True\n"; } else { print "$var7 ($var7 - as an unquoted number) False\n"; } #### $var (0) False $var (undef) False $var1 ('') False $var2 ("") False $var3 (0 - as a single-quoted number) False $var4 (0 - as a double-quoted number) False $var4 (0 - as an unquoted number) True $var4 (0 - as a single-quoted number) True $var4 (0 - as a single-quoted number) has length of 1 and ASCII value of 48 $var5 (1 in single quotes) True $var6 (1 in double quotes) True $var7 (1 - as an unquoted number) True