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Meta-0.08
River stage zero No dependents
/ Meta::Utils::Hash

NAME

Meta::Utils::Hash - general base utility library for many hash functions.

COPYRIGHT

Copyright (C) 2001, 2002 Mark Veltzer; All rights reserved.

LICENSE

This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111, USA.

DETAILS

        MANIFEST: Hash.pm
        PROJECT: meta
        VERSION: 0.35

SYNOPSIS

        package foo;
        use Meta::Utils::Hash qw();
        my(%hash);
        my($size)=Meta::Utils::Hash::size(\%hash);
        # $size should now be 0

DESCRIPTION

This is a general utility perl library for all kinds of hash routines. This mainly iterates hashes using the each builtin which is the fastest to do the job and like the list library uses refernces to avoid duplication whereever possible.

FUNCTIONS

        size($)
        empty($)
        notempty($)
        read($)
        read_exe($)
        cmp($$$$$)
        to_list($)
        add_hash($$)
        remove_hash($$$)
        add_prefix($$)
        add_suffix($$)
        system($$$$)
        dup($)
        add_key_prefix($$)
        add_key_suffix($$)
        filter_prefix($$$)
        filter_prefix_add($$$$)
        filter_multi($$$$)
        filter_suffix($$$)
        filter_regexp($$$)
        filter_regexp_add($$$$)
        filter_file_sing_regexp($$$)
        filter_which($$$)
        filter_exists($)
        filter_notexists($)
        save($$)
        load($$)
        TEST($)

FUNCTION DOCUMENTATION

cmp($$$$$)

This functions compares two hashes according to keys and prints the values which exists in any of them but not in the other The return value is a boolean which is true iff the two hashes are equal. The routine also receives a boolean value telling it to be verbose or not.

to_list($)

This takes a hash reference as input and produces a list which has all the keys in the hash in it. since the keys in the hash are unique the list is unique also...:)

add_hash($$)

This function receives two hashes and adds the second one to the first one the fastest way possible.

remove_hash($$$)

This function receives: 0. A source hash. 1. A hash to remove from the source hash. 2. A strict parameter to tell the function whether to die if an element is in the subtracted hash but not in the source one. The function changes the source hash so as not to contain any elements in the removed hash. The function doesnt return anything.

add_prefix($$)

This routine adds a constant prefix to all the element in a hash. Traversal (ofcourse) is using the each operator

add_suffix($$)

This routine adds a constant suffix to all the element in a hash. Traversal (ofcourse) is using the each operator

add_key_prefix($$)

This routine adds a constant prefix to all the keys in a hash. Traversal (ofcourse) is using the each operator

add_key_suffix($$)

This routine adds a constant suffix to all the keys in a hash. Traversal (ofcourse) is using the each operator.

read($)

This reads a hash table from a file by assuming that every line is a key and giving all the keys a value of undef. That means that the key will exist but the value will be undefined.

read_exe($)

This routine is the same as read except that the argument is a command line to run out of which will come the stdout file that we need to run. Why not just dump the outcome to a temp file and then read it using the previous routine ? because its stupid and uses the disk which we do not need to do... What we do is just pipe the output to a file that we open and execute the same algorithm as before. As it turns out we do call the previous routine but we change the file argument to mean "the stdout stream that comes out of the "$cmd" command"...

filter_prefix($$$)

This routines receives a hash and a prefix and returns a hash with only the elements in the original hash which have such a prefix... This also receives the a third argument that instructs it to act as a negative or a positive filter.

filter_prefix_add($$$$)

This routine filters according to prefix and instruction a certain hash and adds the results to a second.

filter_multi($$$$)

This one is a full filter. This gets: 0. a hash. 1. whether to do filtering or not. 2. boolean indicating whether filter is negative or positive. 3. list of modules for filtering data. And does the entire filtering process in an efficient manner.

filter_suffix($$$)

This routines receives a hash and a suffix and returns a hash with only the elements in the original hash which had such a suffix... This also receives the a third argument that instructs it to act as a negative or a positive filter.

filter_regexp($$$)

This routine filters to the result hash all elements of the hash it gets which match a regular expression. There is also a third argument telling the filter to act as positive or negative.

filter_regexp_add($$$$)

This routine adds to the received hash all the elements of the hash that match/not match (according to the posi argument) elements of the current hash.

empty($)

This routine receives a hash reference. This routine returns a boolean value according to whether the hash is empty or not

notempty($)

This routine receives a hash reference. This routine returns a boolean value accroding to whether the hash is not empty or not

system($$$$)

This routine runs a system command for all keys of a hash. The inputs are: the hash,the system command,demo and verbose.

dup($)

This function receives a hash reference and duplicates it.

size($)

This routine returns the number of elements in the hash (actual elements and not in the strange convention for perl where the size of the array is the number of elements minus 1.

filter_file_sing_regexp($$$)

This routine receives a hash and a regular expression and returns a hash containing only the elements in the hash which are pointers to files which contain a the regular expression. This also receives as the third variable whether to print the matched lines or not (this is passes along to Meta::Utils::File::File::check_sing_regexp).

filter_which()

This needs to be written.

filter_notexists($)

This does the exact opposite of the previous routine. Should we also have the same routine that actually does the manipulation on the list itself ? it would be faster...

save($$)

This routine saves the entire hash to a disk file.

load($$)

This routine loads the entire hash from a disk file.

TEST($)

Test suite for this module. Currently this test creates a small hash table and checks that the size method of this package works.

SUPER CLASSES

None.

BUGS

None.

AUTHOR

        Name: Mark Veltzer
        Email: mailto:veltzer@cpan.org
        WWW: http://www.veltzer.org
        CPAN id: VELTZER

HISTORY

        0.00 MV initial code brought in
        0.01 MV this time really make the databases work
        0.02 MV make quality checks on perl code
        0.03 MV more perl checks
        0.04 MV make Meta::Utils::Opts object oriented
        0.05 MV fix up perl checks
        0.06 MV fix todo items look in pod documentation
        0.07 MV more on tests/more checks to perl
        0.08 MV fix all tests change
        0.09 MV more perl quality
        0.10 MV correct die usage
        0.11 MV perl code quality
        0.12 MV more perl quality
        0.13 MV more perl quality
        0.14 MV perl documentation
        0.15 MV more perl quality
        0.16 MV perl qulity code
        0.17 MV more perl code quality
        0.18 MV more perl quality
        0.19 MV revision change
        0.20 MV languages.pl test online
        0.21 MV PDMT/SWIG support
        0.22 MV perl packaging
        0.23 MV PDMT
        0.24 MV md5 project
        0.25 MV database
        0.26 MV perl module versions in files
        0.27 MV movies and small fixes
        0.28 MV more thumbnail code
        0.29 MV thumbnail user interface
        0.30 MV more thumbnail issues
        0.31 MV website construction
        0.32 MV web site automation
        0.33 MV SEE ALSO section fix
        0.34 MV bring movie data
        0.35 MV md5 issues

SEE ALSO

Meta::IO::File(3), Meta::Utils::File::File(3), Meta::Utils::Output(3), Meta::Utils::Utils(3), strict(3)

TODO

-cant we do the size more efficiently ?

-do the sub filter_file_mult_regexp($$) routine

-the read_exe routine gets a shell command line and sometimes you dont want that overhead. make a routine that does the same and doesnt pass through the shell and check where the current routine is used and replace where ever possible.