question about getopt

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Re: checking $option by targetsmart (Curate) on Jun 26, 2009 at 05:02 UTC
from defined Returns a Boolean value telling whether EXPR has a value other than the undefined value undef. If EXPR is not present, $_ will be checked. you are getting a true boolean value 1, which means when the option is present, you are just storing the return value of defined($options{o}) try ? : `my $source_file = defined($options{o}) ? "<some filename>" : "as.xcf-d +ist" ;` [download] Vivek -- 'I' am not the body, 'I' am the 'soul', which has no beginning or no end, no attachment or no aversion, nothing to attain or lose.	[reply] [d/l]
Re: checking $option by ikegami (Patriarch) on Jun 26, 2009 at 07:34 UTC
This wouldn't be an issue at all if you used the standard module Getopt::Long. Anyway, `my $source_file = defined($options{o}) ? $options{o} : 'as.xcf-dist';` [download] or `my $source_file = 'as.xcf-dist'; $source_file = $options{o} if defined($options{o});` [download] or `my $source_file = $options{o}; $source_file = 'as.xcf-dist' if !defined($options{o});` [download] or `sub defined_or { defined($_[0]) ? $_[0] : $_[1] } my $source_file = defined_or( $options{o}, 'as.xcf-dist' );` [download] or `# Requires 5.10 my $source_file = $options{o} // 'as.xcf-dist';` [download]	[reply] [d/l] [select]
Re: checking $option by citromatik (Curate) on Jun 26, 2009 at 07:38 UTC
If you are using a Perl version >= 5.10 you can also use the `//` operator (see perlop): `my $source_file = $options{o} // 'as.xcf-dist'; my $config_file = $options{c} // 'config.ini'; my $dest_file = $options{x} // usage();` [download] citromatik	[reply] [d/l] [select]
Re: checking $option by leslie (Pilgrim) on Jun 26, 2009 at 05:13 UTC
Dear friend, Check the defined method.It always return boolean value.. If values already defined it will return "true(1)" else "false". If $option is not define it will take the file name and assigned to that variable.. If already defined it will return 1. So u will get 1 as a value..	[reply]
Re: checking $option by Anonymous Monk on Jun 26, 2009 at 05:03 UTC
perldoc -f defined Ieturns a Boolean value telling whether EXPR has a value other than the undefined value undef. If EXPR is not present, $_ will be checked.	[reply]
Re: checking $option by toolic (Bishop) on Jun 26, 2009 at 13:32 UTC
Just to put this thread into context: question about getopt	[reply]


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