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TraceMessages(3)      User Contributed Perl Documentation     TraceMessages(3)

NAME
       Log::TraceMessages - Perl extension for trace messages used in
       debugging

SYNOPSIS
	 use Log::TraceMessages	qw(t d);
	 $Log::TraceMessages::On = 1;
	 t 'got	to here';
	 t 'value of $a	is ' . d($a);
	 {
	     local $Log::TraceMessages::On = 0;
	     t 'this message will not be printed';
	 }

	 $Log::TraceMessages::Logfile =	'log.out';
	 t 'this message will go to the	file log.out';
	 $Log::TraceMessages::Logfile =	undef;
	 t 'and	this message is	on stderr as usual';

	 # For a CGI program producing HTML
	 $Log::TraceMessages::CGI = 1;

	 # Or to turn on trace if there's a command-line argument '--trace'
	 Log::TraceMessages::check_argv();

DESCRIPTION
       This module is a	slightly better	way to put trace statements into your
       code than just calling print().	It provides an easy way	to turn	trace
       on and off for particular sections of code without having to comment
       out bits	of source.

USAGE
       $Log::TraceMessages::On
	   Flag	controlling whether tracing is on or off.  You can set it as
	   you wish, and of course it can be "local"-ized.  The	default	is
	   off.

       $Log::TraceMessages::Logfile
	   The name of the file	to which trace should be appended.  If this is
	   undefined (which is the default), then trace	will be	written	to
	   stderr, or to stdout	if $CGI	is set.

       $Log::TraceMessages::CGI
	   Flag	controlling whether the	program	printing trace messages	is a
	   CGI program (default	is no).	 This means that trace messages	will
	   be printed as HTML.	Unless $Logfile	is also	set, messages will be
	   printed to stdout so	they appear in the output page.

       t(messages)
	   Print the given strings, if tracing is enabled.  Unless $CGI	is
	   true	or $Logfile is set, each message will be printed to stderr
	   with	a newline appended.

       trace(messages)
	   Synonym for "t(messages)".

       d(scalar)
	   Return a string representation of a scalar's	value suitable for use
	   in a	trace statement.  This is just a wrapper for Data::Dumper.

	   "d()" will exit with	'' if trace is not turned on.  This is to stop
	   your	program	being slowed down by generating	lots of	strings	for
	   trace statements that are never printed.

       dmp(scalar)
	   Synonym for "d(scalar)".

       check_argv()
	   Looks at the	global @ARGV of	command-line parameters	to find	one
	   called '--trace'.  If this is found,	it will	be removed from	@ARGV
	   and tracing will be turned on.  Since tracing is off	by default,
	   calling "check_argv()" is a way to make your	program	print trace
	   only	when you ask for it from the command line.

AUTHOR
       Ed Avis,	ed@membled.com

SEE ALSO
       perl(1),	Data::Dumper(3).

POD ERRORS
       Hey! The	above document had some	coding errors, which are explained
       below:

       Around line 218:
	   You forgot a	'=back'	before '=head1'

perl v5.32.0			  2003-12-05		      TraceMessages(3)

NAME | SYNOPSIS | DESCRIPTION | USAGE | AUTHOR | SEE ALSO | POD ERRORS

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