NAME¶
Shell::Perl::Dumper - Dumpers for Shell::Perl
SYNOPSYS¶
use Shell::Perl::Dumper;
$dumper = Shell::Perl::Dumper::Plain->new;
print $dumper->dump_scalar($scalar);
print $dumper->dump_list(@list);
DESCRIPTION¶
In "pirl", the result of the evaluation is transformed into a string
to be printed. As this result may be a pretty complex data structure, the
shell provides a hook for you to pretty-print these answers just the way you
want.
By default, "pirl" will try to convert the results via
"Data::Dump". That means the output will be Perl code that may be
run to get the data structure again. Alternatively, the shell may use
"Data::Dumper" or "Data::Dump::Streamer" with almost the
same result with respect to the representation as Perl code. (But the output
of the modules differ enough for sufficiently complex data.)
Other options are to set the output to produce YAML or a plain simple-minded
solution which basically turns the result to string via simple interpolation.
All of these are implemented via
dumper objects. Dumpers are meant to be
used like that:
$dumper = Some::Dumper::Class->new; # build a dumper
$s = $dumper->dump_scalar($scalar); # from scalar to string
$s = $dumper->dump_list(@list); # from list to string
METHODS¶
The following methods compose the expected API of a dumper, as used by
Shell::Perl.
- new
-
$dumper = $class->new(@args);
Constructs a dumper.
- dump_scalar
-
$s = $dumper->dump_scalar($scalar);
Turns a scalar into a string representation.
- dump_list
-
$s = $dumper->dump_list(@list);
Turns a list into a string representation.
- is_available
-
$ok = $class->is_available
This is an optional class method. If it exists, it means that the
class has external dependencies (like "Shell::Perl::Data::Dump"
depends on "Data::Dump") and whether these may be loaded when
needed. If they can, this method returns true. Otherwise, returning false
means that a dumper instance of this class probably cannot work. This is
typically because the dependency is not installed or cannot be loaded due
to an installation problem.
This is the algorithm used by Shell::Perl XXX XXX XXX
1.
THE STANDARD DUMPERS¶
Shell::Perl provides four standard dumpers:
* Shell::Perl::Data::Dump
* Shell::Perl::Data::Dumper
* Shell::Perl::Data::Dump::Streamer
* Shell::Perl::Dumper::YAML
* Shell::Perl::Dumper::Plain
which corresponds to the four options of the command " :set out ":
"D", "DD", "DDS", "Y", and
"P" respectively.
Data::Dump¶
The package "Shell::Perl::Data::Dump" implements a dumper which uses
Data::Dump to turn Perl variables into a string representation.
It is used like this:
use Shell::Perl::Dumper;
if (!Shell::Perl::Data::Dump->is_available) {
die "the dumper cannot be loaded correctly"
}
$dumper = Shell::Perl::Data::Dump->new;
print $dumper->dump_scalar($scalar);
print $dumper->dump_list(@list);
Examples of its output:
pirl > :set out D
pirl > { a => 3 } #scalar
{ a => 3 }
pirl > (1, 2, "a") #list
(1, 2, "a")
Data::Dumper¶
The package "Shell::Perl::Data::Dumper" implements a dumper which uses
Data::Dumper to turn Perl variables into a string representation.
It is used like this:
use Shell::Perl::Dumper;
if (!Shell::Perl::Data::Dumper->is_available) {
die "the dumper cannot be loaded correctly"
}
$dumper = Shell::Perl::Data::Dumper->new;
print $dumper->dump_scalar($scalar);
print $dumper->dump_list(@list);
Examples of its output:
pirl > :set out DD
pirl > { a => 3 } #scalar
@var = (
{
'a' => 3
}
);
pirl > (1, 2, "a") #list
@var = (
1,
2,
'a'
);
YAML¶
The package "Shell::Perl::Dumper::YAML" implements a dumper which uses
YAML::Syck or YAML to turn Perl variables into a string representation.
It is used like this:
use Shell::Perl::Dumper;
if (!Shell::Perl::Dumper::YAML->is_available) {
die "the dumper cannot be loaded correctly"
}
$dumper = Shell::Perl::Dumper::YAML->new;
print $dumper->dump_scalar($scalar);
print $dumper->dump_list(@list);
Examples of its output:
pirl > :set out Y
pirl @> { a => 3 } #scalar
---
a: 3
pirl @> (1, 2, "a") #list
--- 1
--- 2
--- a
When loading, "YAML::Syck" is preferred to "YAML". If it is
not available, the "YAML" module is the second option.
Data::Dump::Streamer¶
The documentation is yet to be written.
Plain Dumper¶
The package "Shell::Perl::Dumper::Plain" implements a dumper which
uses string interpolation to turn Perl variables into strings.
It is used like this:
use Shell::Perl::Dumper;
$dumper = Shell::Perl::Dumper::Plain->new;
print $dumper->dump_scalar($scalar);
print $dumper->dump_list(@list);
Examples of its output:
pirl > :set out P
pirl > { a => 3 } #scalar
HASH(0x1094d2c0)
pirl > (1, 2, "a") #list
1 2 a
SEE ALSO¶
Shell::Perl
BUGS¶
Please report bugs via CPAN RT
<
http://rt.cpan.org/NoAuth/Bugs.html?Dist=Shell-Perl> or
<
mailto://bugs-Shell-Perl@rt.cpan.org>.
AUTHORS¶
Adriano R. Ferreira, <ferreira@cpan.org>
Caio Marcelo, <cmarcelo@gmail.com>
COPYRIGHT AND LICENSE¶
Copyright (C) 2007X2011 by Adriano R. Ferreira
This library is free software; you can redistribute it and/or modify it under
the same terms as Perl itself.