As it was, it could break if the argument was repeated more than twice.
When checking dot patterns, we need to check that no further holes are
solved, and that the pattern variable doesn't unify with some other
pattern variable, but if it had already made progress (either for a good
or bad reason) we missed this. Fixes#536
As it was, there was significant backtracking for big expressions,
getting to the end, not finding a **, so having to try again for
application expressions. Fixes#532
This has involved quite a bit of reorganisation and some improvements in
resugaring so that the results look nice. In summary:
* Expression search now gives back a RawImp rather than a checked term,
which allows it to include case expressions
* Case with one pattern is resugared to a destructuring let
* Some name generation issues address in function generation
We look at intermediate results for local variables which are functions
that return a concrete type, or recursive calls that return a single
constructor type. In these cases, we:
* let bind the local variable/recursive call
* generate a new definition for the scope, as a 'case' function
When we recursively generate the definition, it's a bit more restricted
so as not to explode the search space. We only take the first result, we
only look one constructor deep, and we go right to left on variable
splitting so only deconstruct the name we've just added.
These continue the search from :ps and :gd next respectively, giving the
next search result until there are no more results.
Correspondingly, added ':proof-search-next' and ':generate-def-next' in
IDE mode, which continue the search from the previous ':proof-search'
and ':generate-def' respectively.
...until the definition is complete. This is necessary since sometimes
information outside the case block can help resolve interfaces, and in
the simplest case, we might just have delayed resolving a default
Integer. It turns out this was also an obscure bug waiting to happen
with coverage checking of nested case blocks (so there's a test update
there too).
Fixes#443
In a 'Bind', normalise the result of the first action, rather than
quoting the HNF. This improves performance since the HNF could be quite
big when quoted back.
Ideally, we wouldn't have to quote and unquote here, and we can probably
achieve this by tinkering with the evaluator.
This has an unfortunate effect on the reflection002 test, in that the
"typed template Idris" example now evaluates too much. But, I think the
overall performance is too important for the primary motivation
behind elaborator reflection. I will return to this!
Instead of just the cursory name update that we used to do (which didn't
work properly anyway for a lot of reasons), now we add aliases for all
the names in the imported module.
So, like Idris 1, every global has a canonical name by which we can
refer to it, but it can also have aliases via "import ... as".
If we have a delayed thing, but we don't yet know the expected type,
don't commit to forcing because the expected type might turn out to be a
delay.
Fixes#395
'convert' doesn't solve holes, so might reject things that are solvable.
This can be an issue when resolving interfaces, because we were using
convert for arguments of the invertible holes that arise when trying to
resolve them. Fixes#66.
We need to make sure they are inferred again when elaborating methods,
so substitute in a _ in method types before substituting in the explicit
parameters.
In future, it might (probably will) also be useful to allow giving the
implicit parameters explicitly when defining implementations.
Fixes#374
We need to check below top level too, since there could be holes that
we're happy to resolve by searching. The linearity test added
illustrates a place where this is needed.