NAME

       Devel::Cover::Truth_Table - Truth tables for coverage objects.

VERSION

       version 1.21

SYNOPSIS

         use Devel::Cover::Truth_Table;

         # $a || $b
         my $or_tt  = Devel::Cover::Truth_Table->new_primitive('or_3', 0, 1, 1);

         # $c && $d
         my $and_tt = Devel::Cover::Truth_Table->new_primitive('and_3', 1, 0, 1);

         # merge contents of $and_tt into right column of $or_tt, to create
         # $a || ($c && $d)
         $or_tt->right_merge($and_tt);

         # get a (sorted) textual representation
         my @text = $or_tt->sort->text;
         print "$_\n" foreach @text;

         __END__
         A B C |exp|hit
         --------------
         0 0 X | 0 |---
         0 1 0 | 0 |---
         0 1 1 | 1 |+++
         1 X X | 1 |+++
         --------------

DESCRIPTION

       This module provides methods for creating and merging conditional primitives ("$a && $b",
       "$c || $d", etc.) into more complex composite expressions.

METHODS

   new_primitive($op, @coverage)
       Create a new truth table based on one of the built-in primitives, which are the subclasses
       of Devel::Cover::DB::Condition. $op is one of the following:

       and_3
           "and" or "&&" with three conditional paths.

       or_3
           "or" or "||" with three conditional paths.

       or_2
           "or" or "||" with two conditional paths. (i.e., when the right hand side of the
           expression is a constant)

       xor_4
           "xor" with four conditional paths.

       @coverage is a list booleans identifying which of the possible paths have been covered.

   sort()
       Sorts a truth table (in place) and returns the sorted object.

   text()
       Format a truth table to an array of strings for printing.

   html()
       Format a truth table in HTML.

   error()
   percentage()
       Determines the proportion of possible conditions that have coverage.

   right_merge($sub_table)
       Merge entries from $sub_table into right column of table.

   left_merge($sub_table)
       Merge entries from $sub_table into left column of table.

SEE ALSO

       Devel::Cover

BUGS

       None that I'm aware of...

LICENSE

       Copyright 2002 Michael Carman <mjcarman@mchsi.com>

       This software is free. It is licensed under the same terms as Perl itself. The latest
       version should be available from: http://www.pjcj.net