If not specified (strict), the search is sucessful if
the WLD is within a calculated limit where each insertion,
deletion and replacement adds a weight to a common pool of
weights. This is the mathematically correct WLD.
From a user's point of view the strict WLD is an
exclusive-OR of the arguments given, for example if allowed
insertions=2 and allowed replacements=2, the search fails if 2
characters had been inserted and an additional operation would
be needed to match. Depending on the weights it may also fail if
1 character was inserted and 1 character replaced and an
additional operation would be needed to match. The strict
algorithm may match less than expected from a first glance of
the specified arguments, but does not return false positives.
If specified (relaxed), the search is also successful
if the combined pool for insertions and deletions is below a
doubled calculated limit and replacements are treated
differently. Additionally, swapped characters are counted as one
replacement.
From a user's point of view the relaxed WLD is an
inclusive-OR of the arguments given, for example if allowed
insertions=2 and allowed replacements=2, the search succeeds if
2 characters had been inserted and an additional replacement is
needed to match. The relaxed algorithm may return false
positives, but meets user expectation better.