NAME¶
Number::Tolerant::Union - unions of tolerance ranges
VERSION¶
version 1.703
SYNOPSIS¶
use Number::Tolerant;
my $range1 = tolerance(10 => to => 12);
my $range2 = tolerance(14 => to => 16);
my $union = $range1 | $range2;
if ($11 == $union) { ... } # this will happen
if ($12 == $union) { ... } # so will this
if ($13 == $union) { ... } # nothing will happen here
if ($14 == $union) { ... } # this will happen
if ($15 == $union) { ... } # so will this
DESCRIPTION¶
Number::Tolerant::Union is used by Number::Tolerant to represent the union of
multiple tolerances. A subset of the same operators that function on a
tolerance will function on a union of tolerances, as listed below.
METHODS¶
new¶
my $union = Number::Tolerant::Union->new(@list_of_tolerances);
There is a "new" method on the Number::Tolerant::Union class, but
unions are meant to be created with the "|" operator on a
Number::Tolerant tolerance.
The arguments to "new" are a list of numbers or tolerances to be
unioned.
Intersecting ranges are not converted into a single range, but this may change
in the future. (For example, the union of "5 to 10" and "7 to
12" is not "5 to 12.")
options¶
This method will return a list of all the acceptable options for the union.
Overloading¶
Tolerance unions overload a few operations, mostly comparisons.
- numification
- Unions numify to undef. If there's a better idea, I'd love to hear
it.
- stringification
- A tolerance stringifies to a short description of itself. This is a set of
the union's options, parentheses-enclosed and joined by the word
"or"
- equality
- A number is equal to a union if it is equal to any of its options.
- comparison
- A number is greater than a union if it is greater than all its options.
A number is less than a union if it is less than all its options.
- union intersection
- An intersection ("&") with a union is commutted across all
options. In other words:
(a | b | c) & d ==yields==> ((a & d) | (b & d) | (c & d))
Options that have no intersection with the new element are dropped. The
intersection of a constant number and a union yields that number, if the
number was in the union's ranges and otherwise yields nothing.
TODO¶
Who knows. Collapsing overlapping options, probably.
AUTHOR¶
Ricardo Signes <rjbs@cpan.org>
COPYRIGHT AND LICENSE¶
This software is copyright (c) 2004 by Ricardo Signes.
This is free software; you can redistribute it and/or modify it under the same
terms as the Perl 5 programming language system itself.