GT::Dumper - Convert Perl data structures into a string.
use GT::Dumper;
print Dumper($complex_var);
print GT::Dumper->dump ( var => '$MYVAR', data => $complex_var);
GT::Dumper by default exports a method Dumper() which will
behave similar to Data::Dumper's Dumper(). It differs in that
it will only take a single argument, and the variable dumped
will be $VAR instead of $VAR1. Also, to provide easier control
to change the variable name that gets dumped, you can use:
GT::Dumper->dump ( var => string, data => yourdata );
and the dump will start with string = instead of $VAR = .
use GT::Dumper;
my %foo;
my @bar = (1, 2, 3);
$foo{alpha} = \@bar;
$foo{beta} = 'a string';
print Dumper(\%foo);
This will print:
$VAR = {
'beta' => 'a string',
'alpha' => [
'1',
'2',
'3',
],
};
Dumper() is exported by default when using GT::Dumper. It takes a single
variable and returns a string representation of the variable. The string can
then be eval()'ed back into the same data structure.
It takes only one argument - the variable to dump. The return is a string of the form:
$VAR = DATA
where 'DATA' is the actual data structure of the variable. A more powerful and customizable dumping method is the dump method.
dump() provides a more customizable method to dumping a data structure. Through
the various options available, listed below, the output of a data structure
dump can be formatted in several different ways.
The options are as follows. Only the data option is required.
$VAR. For example, dumping
the string foo would return: $VAR = 'foo'. You can change and even omit
the assignment using the var option. To specify a different variable, you
simply specify it as the value here. To have 'foo' dump as just 'foo'
instead of $VAR = 'foo', specify var as an empty string, or undef.
tab option.
sort option enables hash key sorting. It is not on by default - to
enable, simply specify the sort option with 1 as the value. The default sort
method is case-sensitive alphabetical. See the order option for
specifying your own sort order.
order option takes a code
reference and enables custom sort ordering. The code reference will be passed 4
variables. The first and second are the two items being compared - $a and $b in
Perl's sort mechanism. The third and fourth are the values in the hash being
sorted. The code reference, like a Perl sort routine, should return -1 if $a
should come before $b, 0 if $a and $b are equivelant in your sort order, and 1
if $b should come before $a. Because of scoping and package issues in Perl, it
is not possible to directly use $a and $b.
Compression removes all non-essential characters from the output, thus reducing data size, however also generally making the dump very difficult to read. If enabled, the dumping behaviour is changed as follows:
$VAR = DATA), the spaces around the = will be stripped.
The output will look like: $VAR=DATA
var option is
ignored - it is treated as if a blank var was entered, thereby not returning
an assignment. The other difference is that an an ordinary dump adds a
semicolon and newline at the end of the dump, but these are not added when the
structure option is enabled.
This is a quick method to do a structure dump. It takes one argument - the data to dump. Calling: $class->dump_structure($DATA); is identical to calling: $class->dump(data => $DATA, structure => 1); See the structure option.
Jason Rhinelander
Copyright (c) 2004 Gossamer Threads Inc. All Rights Reserved. http://www.gossamer-threads.com/
Revision: $Id: Dumper.pm,v 1.38 2005/02/18 04:44:33 jagerman Exp $