algorithm::dependency::source::file(3pm) [debian man page]

Algorithm::Dependency::Source::File(3pm)		User Contributed Perl Documentation		  Algorithm::Dependency::Source::File(3pm)

NAME

       Algorithm::Dependency::Source::File - File source for dependency heirachys

DESCRIPTION

       Algorithm::Dependency::Source::File implements a source where the items are stored in a flat file or a relatively simple format.

   File Format
       The file should be an ordinary text file, consisting of a series of lines, with each line completely containing the information for a
       single item.  Blank lines, or lines beginning with the hash character '#' will be ignored as comments.

       For a single item line, only word characters will be used. A 'word character' consists of all letters and numbers, and the underscore '_'
       character.  Anything that is not a word character will be assumed to be a seperator.

       The first word will be used as the name or id of the item, and any further words in the line will be used as other items that this one
       depends on. For example, all of the following are legal.

	 # A single item with no dependencies
	 Foo

	 # Another item that depends on the first one
	 Bar Foo

	 # Depending on multiple others
	 Bin Foo Bar

	 # We can use different seperators
	 One:Two|Three-Four+Five=Six Seven

	 # We can also use multiple non-word characters as seperators
	 This&*&^*&File:  is& & & :::REALLY()Neat

       From the examples above, it should be easy to create your own files.

METHODS

       This documents the methods differing from the ordinary Algorithm::Dependency::Source methods.

   new $filename
       When constructing a new Algorithm::Dependency::Source::File object, an argument should be provided of the name of the file to use. The
       constructor will check that the file exists, and is readable, returning "undef" otherwise.

SUPPORT

       To file a bug against this module, use the CPAN bug tracking system

       http://rt.cpan.org/NoAuth/ReportBug.html?Queue=Algorithm-Dependency <http://rt.cpan.org/NoAuth/ReportBug.html?Queue=Algorithm-Dependency>

       For other comments, contact the author.

AUTHOR

       Adam Kennedy <adamk@cpan.org>

SEE ALSO

       Algorithm::Dependency

COPYRIGHT

       Copyright 2003 - 2009 Adam Kennedy.

       This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

       The full text of the license can be found in the LICENSE file included with this module.

perl v5.12.4							    2009-04-14				  Algorithm::Dependency::Source::File(3pm)

CPANDB::Dependency(3pm) 				User Contributed Perl Documentation				   CPANDB::Dependency(3pm)

NAME

       CPANDB::Dependency - CPANDB class for the dependency table

DESCRIPTION

       TO BE COMPLETED

METHODS

   base
	 # Returns 'CPANDB'
	 my $namespace = CPANDB::Dependency->base;

       Normally you will only need to work directly with a table class, and only with one ORLite package.

       However, if for some reason you need to work with multiple ORLite packages at the same time without hardcoding the root namespace all the
       time, you can determine the root namespace from an object or table class with the "base" method.

   table
	 # Returns 'dependency'
	 print CPANDB::Dependency->table;

       While you should not need the name of table for any simple operations, from time to time you may need it programatically. If you do need
       it, you can use the "table" method to get the table name.

   load
	 my $object = CPANDB::Dependency->load( $distribution );

       If your table has single column primary key, a "load" method will be generated in the class. If there is no primary key, the method is not
       created.

       The "load" method provides a shortcut mechanism for fetching a single object based on the value of the primary key. However it should only
       be used for cases where your code trusts the record to already exists.

       It returns a "CPANDB::Dependency" object, or throws an exception if the object does not exist.

   select
	 # Get all objects in list context
	 my @list = CPANDB::Dependency->select;

	 # Get a subset of objects in scalar context
	 my $array_ref = CPANDB::Dependency->select(
	     'where distribution > ? order by distribution',
	     1000,
	 );

       The "select" method executes a typical SQL "SELECT" query on the dependency table.

       It takes an optional argument of a SQL phrase to be added after the "FROM dependency" section of the query, followed by variables to be
       bound to the placeholders in the SQL phrase. Any SQL that is compatible with SQLite can be used in the parameter.

       Returns a list of CPANDB::Dependency objects when called in list context, or a reference to an "ARRAY" of CPANDB::Dependency objects when
       called in scalar context.

       Throws an exception on error, typically directly from the DBI layer.

   iterate
	 CPANDB::Dependency->iterate( sub {
	     print $_->distribution . "
";
	 } );

       The "iterate" method enables the processing of large tables one record at a time without loading having to them all into memory in advance.

       This plays well to the strength of SQLite, allowing it to do the work of loading arbitrarily large stream of records from disk while
       retaining the full power of Perl when processing the records.

       The last argument to "iterate" must be a subroutine reference that will be called for each element in the list, with the object provided in
       the topic variable $_.

       This makes the "iterate" code fragment above functionally equivalent to the following, except with an O(1) memory cost instead of O(n).

	 foreach ( CPANDB::Dependency->select ) {
	     print $_->distribution . "
";
	 }

       You can filter the list via SQL in the same way you can with "select".

	 CPANDB::Dependency->iterate(
	     'order by ?', 'distribution',
	     sub {
		 print $_->distribution . "
";
	     }
	 );

       You can also use it in raw form from the root namespace for better control.  Using this form also allows for the use of arbitrarily complex
       queries, including joins. Instead of being objects, rows are provided as "ARRAY" references when used in this form.

	 CPANDB->iterate(
	     'select name from dependency order by distribution',
	     sub {
		 print $_->[0] . "
";
	     }
	 );

   count
	 # How many objects are in the table
	 my $rows = CPANDB::Dependency->count;

	 # How many objects
	 my $small = CPANDB::Dependency->count(
	     'where distribution > ?',
	     1000,
	 );

       The "count" method executes a "SELECT COUNT(*)" query on the dependency table.

       It takes an optional argument of a SQL phrase to be added after the "FROM dependency" section of the query, followed by variables to be
       bound to the placeholders in the SQL phrase. Any SQL that is compatible with SQLite can be used in the parameter.

       Returns the number of objects that match the condition.

       Throws an exception on error, typically directly from the DBI layer.

ACCESSORS

   distribution
	 if ( $object->distribution ) {
	     print "Object has been inserted
";
	 } else {
	     print "Object has not been inserted
";
	 }

       Returns true, or throws an exception on error.

       REMAINING ACCESSORS TO BE COMPLETED

SQL

       The dependency table was originally created with the following SQL command.

	 CREATE TABLE dependency (
	     distribution TEXT NOT NULL,
	     dependency TEXT NOT NULL,
	     phase TEXT NOT NULL,
	     core REAL NULL,
	     PRIMARY KEY (distribution,
	     dependency,
	     phase),
	     FOREIGN KEY (distribution) REFERENCES distribution (distribution),
	     FOREIGN KEY (dependency) REFERENCES distribution (distribution)
	 )

SUPPORT

       CPANDB::Dependency is part of the CPANDB API.

       See the documentation for CPANDB for more information.

AUTHOR

       Adam Kennedy <adamk@cpan.org>

COPYRIGHT

       Copyright 2009 - 2011 Adam Kennedy.

       This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

       The full text of the license can be found in the LICENSE file included with this module.

perl v5.14.2							    2011-11-25						   CPANDB::Dependency(3pm)