main and external script

spadacciniweb has asked for the wisdom of the Perl Monks concerning the following question:

I have a main program named "mal.pl" as:

1   #!/usr/bin/perl -w
2 
3   push @INC, ".";
4   require "config.conf";
5..7
8   print $verbose;
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and in the same directory, the file "config.conf" as

1   $verbose = 1;
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Question: if run "mal.pl"... why the output is:

  Name "main::verbose" used only once: possible typo at ./mal.pl line 
+8.
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thank you

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Re: main and external script by ikegami (Patriarch) on Dec 02, 2005 at 18:15 UTC
Sorry, I don't have an answer to your question. However, I do have a tip: When including Perl files without a `package`, you should use `do`, not `require` or `use`.	[reply] [d/l] [select]
Re: main and external script by gu (Beadle) on Dec 02, 2005 at 18:52 UTC
At compile time, $verbose is used only once... To fix your problem you can write : `#!/usr/bin/perl -w BEGIN{require "config.conf"} ; print $verbose ;` [download] But as ikegami said `do` is better. Furthermore, you should write `our $verbose = 1;` in the required file to give it an appropriate scope. Gu	[reply] [d/l] [select]
Re: main and external script by psychotic (Beadle) on Dec 02, 2005 at 19:16 UTC
If you are creating a module to include configuration information, you might find the following useful. Firstly, we create the module that holds the configuration information, making sure the proper things are exported. Source: `package Testing; use strict; use Exporter; our @ISA = qw(Exporter); our (%EXPORT_TAGS); $EXPORT_TAGS{'config'} = [qw($verbose $debug)]; Exporter::export_ok_tags('config'); our ($verbose, $debug) = (1,1); 1;` [download] And the main script that exploits the configuration information: `use strict; use warnings; use Testing qw(:config); print "I am ", $verbose ? "" : "not ", "verbose\n"; print "I should ", $debug ? "" : "not ", "debug\n";` [download] When the code directly above is run, it produces, as expected: `I am verbose I should debug` [download] For instance, if we changed this line ( `our ($verbose, $debug) = (1,1);` ) in the configuration module, to ( `our ($verbose, $debug) = (undef,undef);` ) we would get: `I am not verbose I should not debug` [download]	[reply] [d/l] [select]
Re^2: main and external script by gu (Beadle) on Dec 02, 2005 at 19:19 UTC
Or you can use the great Damian Conways' Config::Std. Really good one. Gu	[reply]


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