Hello Monks,
I wrote a primitive parser of a simple configuration file, and I wrote some Perl that generates warnings. In my head, the two variable definitions are in different scopes, but the interpreter doesn't think the same way I do. It seemed to me that, since the if and elsif clauses can never be executed simultaneously, the my declarations are in different lexical scopes. Also, once we leave the if/elsif/else blocks, the temporary variables are out of scope, so there could never be confusion as to whether they were defined in the if or the elsif.
Can someone explain to me why it works this way?
#!/usr/bin/perl use warnings; use strict; my (%foos, %bars); while( my $line = <DATA> ) { chomp $line; if ( my ( $key, $val ) = $line =~ /^foo ([^:]*):([^:]*)$/ ) { push( @{ $foos{ $key } }, $val ); } elsif ( my ( $key, $val ) = $line =~ /^bar ([^:]*):([^:]*)$/ ) { push( @{ $bars{ $key } }, $val ); } else { # warn qq( "$line" is the wrong format.\n ); } } __DATA__ foo key1:val1 bar key2:val2 foo key3:val3 bar key4:val4 3 bad:val
"my" variable $key masks earlier declaration in same scope at ./test.pl line 11. "my" variable $val masks earlier declaration in same scope at ./test.pl line 11.
In reply to lexical scope in if/elsif tests by AR
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