NAME

Devel::Cover::Truth_Table - Create and manipulate truth tables for coverage objects.

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.