/ 
App-Pebble-0.003-TRIAL
River stage zero No dependents
/ App::Pebble

NAME

App::Pebble - Unix like streams, but with objects instead of lines of text

DESCRIPTION

The Unix idea of a stream of lines, on steroids.

Note: This is alpha, pure R&D at this stage; just trying out a good way to do things.

SYNOPSIS

Work with lines of text

# pgrep, pn: Filter out POD lines, add a \n
cat lib/App/Pebble.pm | pebble 'pgrep { /^=/ } | pn'
=head1 NAME
=head1 SYNOPSIS
=head1 DESCRIPTION
...

# The same, limit output to 2 lines
cat lib/App/Pebble.pm | p 'pgrep { /^=head/ } | plimit 2 | pn'
=head1 NAME
=head1 SYNOPSIS

Work with objects

# P->match: Parse matching lines into objects with named attributes.
# The default output format is one-line JSON.
cat lib/App/Pebble.pm | \
p 'P->match( regex => qr/^=head(\d+)\s+(.+)/, has => ["level", "text"] )'
{"level":"1","text":"NAME"}
{"level":"1","text":"SYNOPSIS"}
{"level":"1","text":"DESCRIPTION"}
...

###TODO: split

###TODO: parsers

# R->table: Do the same, but provide a Renderer (table) as the final stage
cat lib/App/Pebble.pm | \
p 'P->match( regex => qr/^=head(\d+)\s+(.+)/, has => ["level", "text"] ) | R->table'
.-------------------------------.
| level | text                  |
+-------+-----------------------+
|     1 | NAME                  |
|     1 | SYNOPSIS              |
|     1 | DESCRIPTION           |
...
'-------+-----------------------'

# --out=CSV: Do the same, but provide a CSV renderer on the command line,
# not as the final stage.
# You can install more renderers, and write your own.
cat lib/App/Pebble.pm | \
p --out=CSV 'P->match( regex => qr/^=head(\d+)\s+(.+)/, has => ["level", "text"] )'
level,text
1,NAME
1,SYNOPSIS
1,DESCRIPTION

Filtering objects

# pgrep: Filter out headings with too long text
cat lib/App/Pebble.pm | \
p --out=table 'P->match( regex => qr/^=head(\d+)\s+(.+)/, has => ["level", "text"] )
| pgrep { length( $_->text) < 5 }'
.--------------.
| level | text |
+-------+------+
|     1 | NAME |
|     1 | BUGS |
'-------+------'

Transforming objects

# p / pmap: Shorten the text value to at most 5 chars
# "pmap" is so commonly used it's aliased to "p" for convenience.
# Note that you still want the object itself to be passed along in the stream,
# so you need to end the block with $_;
cat lib/App/Pebble.pm | p --out=table 'P->match( regex => qr/^=head(\d+)\s+(.+)/, has => ["level", "text"] ) | p { $_->text( substr($_->text, 0, 5 )); $_ }'
.---------------.
| level | text  |
+-------+-------+
|     1 | NAME  |
|     1 | SYNOP |
|     1 | DESCR |
...

###TODO: local variables

Work with predefined commands

# --cmd=df: Run "df -k" and parse the output
p --cmd=df --out=table 'plimit 2'
.--------------------------------------------------------------------------.
| available | blocks    | capacity | filesystem   | mounted_on | used      |
+-----------+-----------+----------+--------------+------------+-----------+
|  21856800 | 976101344 |       98 | /dev/disk0s2 | /          | 953732544 |
|         0 |       216 |      100 | devfs        | /dev       |       216 |
'-----------+-----------+----------+--------------+------------+-----------'

CLASS ATTRIBUTES

cache[ Cache::Cache | undef ]

Optional cache object, used for e.g. web requests.

METHODS

AUTHOR

Johan Lindstrom, <johanl at cpan.org>

BUGS

Please report any bugs or feature requests to bug-app-pebble at rt.cpan.org, or through the web interface at http://rt.cpan.org/NoAuth/ReportBug.html?Queue=App-Pebble. I will be notified, and then you'll automatically be notified of progress on your bug as I make changes.

SUPPORT

You can find documentation for this module with the perldoc command.

perldoc App::Pebble

You can also look for information at:

ACKNOWLEDGEMENTS

LICENSE AND COPYRIGHT

Copyright 2010- Johan Lindstrom.

This program is free software; you can redistribute it and/or modify it under the terms of either: the GNU General Public License as published by the Free Software Foundation; or the Artistic License.

See http://dev.perl.org/licenses/ for more information.