NAME

Tree::Range::conflict – override range_set, so that it fails instead of writing over

SYNOPSIS

    package Tree::Range::Foo::Conflict 0.022;

    require Tree::Range::conflict;
    require Tree::Range::Foo;

    push (our @ISA, qw (Tree::Range::conflict Tree::Range::Foo));

DESCRIPTION

This class overrides the range_set method, adding a guard which raises an exception (i. e., dies) if the range being associated is already given a value or values other than the leftmost one (as determined by the range_free_p method.)

Consider, e. g.:

    ## assuming numeric (<=>) comparison function
    $rat->range_set (100, 200, "foo");
    $rat->range_set (200, 300, "bar");
    $rat->range_set (150, 250, "baz");

The last range_set invocation in the example above raises an exception if the class of $rat is a descendant of this one.

Note, however, that the range_set_over method is not overridden, so it’s still possible to overwrite an arbitrary range’s association, or to effectively “remove” one (by associating it with the leftmost value.)

SEE ALSO

Tree::Range::base, Tree::Range::RB::Conflict

AUTHOR

Ivan Shmakov <oneingray@gmail.com>

This library is free software; you can redistribute it and/or modify it under the terms of the 3-clause BSD license, as included within the code.