This refactor simplifies the desugar pass by reducing the number of
arguments threaded through each recursive function call.
- Add the module src string to `Env`.
- Add `line_info` to `Env` as a lazy-evaled function.
- Refactor desugar functions to take the `can::Env` struct in place of a
number of params. This is mostly a find-and-replace, but in a few
places `Vec::from_iter_in` was changed to `Vec::with_capacity_in`
followed by a `for` loop in order to avoid lifetime issues.
- Remove unnecessary linter annotations for `clippy::too_many_arguments`
Fix a bug in `dbg` expression desugaring by using the module scope to
generate unique identifiers instead of the variable store.
In the initial implementation of `dbg` expressions we used the
`VarStore` to generate unique identifiers for new variables created
during desugaring. We should have instead used the current module's
`Scope`, which handles identifiers within the module. Each scope has its
own incrementing variable count which is independent of the shared
variable store. The scope is used to generate new identifiers at other
points in canonicalization, such as when assigning a global identifier
to closures and `expect`s. It's possible that the identifier generated
for `dbg` could conflict with an identifier generated by the scope,
resulting in a confusing error.
We were still passing `ModuleIds` from `load` to `can`, but now
that imports can appear in any scope, we don't know which package
an unqualified module name belongs to from the top level.
We now pass `PackageModuleIds` instead and keep a Map of `ModuleName` to
`ModuleId` in `Scope`.
This also allow us to import multiple modules with the same name from different
packages as long as a unique alias is provided.
Moves handling of ingested file imports from load to can, so that they
can be properly introduced in the scope they appear.
Example:
import "input.txt" as input : Str
image =
import "image.png" as bytes : List U8
# `bytes` is only available under `image`
decodePng bytes
...
