On 04/12/2019 00:17, fo...@univ-mlv.fr wrote:
I don't follow you, conceptually a pattern matching is an optional of
tuples (i don't want to go more deep than that given that the real
implementation is still in flux), you can construct an optional if
getReturnComponents() returns null or not.
Right - but what happens when you do:
Class<?> x = ...
if (x instanceof Class.recordComponents(var components)) {
...
}
If the method Class::getRecordComponents always returns something (e.g.
an empty array) and we claim that a deconstructor here is the dual case
of that, that might suggest that the pattern above always matches (in
some cases with 'components' bound to an empty array). My guts is that
people writing the above code will want it NOT to match if 'x' is not a
record class; but if you go there, then you have what seems like an
asymmetry: I can ask String.class.getRecordComponents (and get an empty
array) but I can pattern-match String.class, because the extractor also
does the 'isRecord' trick, and fail to match if that returns false.
Not saying it's not doable... but feels more awkward for some reason.
Maurizio
