[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
How difficult would it be to extend the matcher to pattern matching?
Ignore issue of syntax, I imagine a special kind of "pattern variable box".
When the pattern variable box is matched against a Scheme value, then
the match always succeeds, and the value is saved in the box, where it
can be used later.
A useful extension is to allow the pattern variable box to have a type
predicate: basically any one-argument function. In that case the match
only succeeds if the applying the predicate to the variable returns true.
And then the extension I really want: sub-sequence matching. I.e. matching
of regular trees. Basically pattern boxes that match a variable number of
elements in a list or vector.