As part of making tuples first-class citizens, expliciting the arity upon
function application was needed (so that a function of two args can
transparently -- in the surface language -- be applied to either two arguments
or a pair).
It was decided to actually explicit the whole type of arguments because the cost
is the same, and this is consistent with lambda definitions.
A related change done here is the replacement of the `EOp` node for operators by
an "operator application" `EAppOp` node, enforcing a pervasive invariant that
operators are always directly applied. This makes matches terser, and highlights
the fact that the treatment of operator application is almost always different
from function application in practice.
Added a new type safety invariant to ensure that the type `TDefault` can only appear in certain positions,
* On the left-hand side of an arrow with arity 1, as the type of a scope (for scope calls).
* At the root of the type tree (outside a default).
* On the right-hand side of the arrow at the root of the type (occurs for rentrant variables).
This is crucial to maintain the safety of the type system, as demonstrated in the formal development.
The invariant was checked on all tests cases and on family and housing benefits.
Adjusted inversion invariant about app to handle external objects as well.
This changes the `decl_ctx` to be toplevel only, with flattened references to
uids for most elements. The module hierarchy, which is still useful in a few
places, is kept separately.
Module names are also changed to UIDs early on, and support for module aliases
has been added (needs testing).
This resolves some issues with lookup, and should be much more robust, as well
as more convenient for most lookups.
The `decl_ctx` was also extended for string ident lookups, which avoids having
to keep the desugared resolution structure available throughout the compilation
chain.
- Add a `-I` option that allows defined modules to be available from other
directories
- Add reporting of the number of successful / failed tests
- Locate the project root, and always run the commands from there
