Add support for directions on parameters and attributed types. The
latter is necessary to support the former, but is not limited to
the direction use case. An attributed type is a P4 type with attributes
(like its direction, whether it is read only, etc.) Other attributes
will be added in the future.
Changes necessary to support attributed types include:
1. Global instances tracked during compilation are not attributed
types and not simply types.
2. (future) Type checking will have to make sure that a types
attributes do not affect type compatibility.
Signed-off-by: Will Hawkins <hawkinsw@obs.cr>
By adding an expected type to the compilation context, it is
now possible for type checking to occur on keyset expressions
and return statements at the moment that they are being compiled.
Previously, it was necessary to tentatively compile them and then
typecheck afterward.
Signed-off-by: Will Hawkins <hawkinsw@obs.cr>
1. Add support for field access
2. Add support for proper type checking of array access
3. Add tests for nested field and array access
Signed-off-by: Will Hawkins <hawkinsw@obs.cr>
update method will allow the creation of a new compilation context
based on the current one with new types/names.
Signed-off-by: Will Hawkins <hawkinsw@obs.cr>
Compilation interface(s) now contain a compilation context.
The change will make it easier to expand on what each step
of the compilation process needs to know to complete its task
without having to make major changes to the interface.
Signed-off-by: Will Hawkins <hawkinsw@obs.cr>
Do not pass around the MutableTree -- now that we are not
using queries for walking the AST, it is unnecessary.
Signed-off-by: Will Hawkins <hawkinsw@obs.cr>
Will Hawkins