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hoe-jo
commented
Mar 3, 2026
hoe-jo
commented
- Add Implementation
- Add System Tests
- Add Documentation
- Update LRM
- Add Implementation - Add System Tests - Add Documentation - Update LRM
| #### union_partial_field_access | ||
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| Accessing a field on a union type that does not exist in all member | ||
| types is allowed but may return `null` at run-time. The linter warns |
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Small formatting issue: there are two spaces in
“run-time. The linter warns...”
| types may not appear in a union type.''' | ||
| } | ||
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| Static_Semantics Union_Type_No_Field_Access { |
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Name is a bit confusing. Rule name says “No_Field_Access”, but text says field access is allowed in some cases.
| # lobster-trace: LRM.Valid_Index_Prefixes | ||
| self.mh.error(n_name.location, | ||
| "expression '%s' has type %s, " | ||
| "which is not a tuple or record" % |
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Suggestion: change to "which is not a tuple, record, or union".
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| # We can now perform the access on the record value | ||
| field_map = prefix_typ.get_field_map() | ||
| union_id = "_".join(t.name for t in prefix_typ.types) |
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This needs one more system test.
union SMT names are built only from short type names.
If two packages have same type names, generated SMT names can clash.
Please add a cross-package test with same short type names to make sure no collision happens.
| # We can compary anything to null (including itself) | ||
| pass | ||
| elif isinstance(self.n_lhs.typ, Union_Type) or \ | ||
| isinstance(self.n_rhs.typ, Union_Type): |
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Should equality between a union-typed reference and an unrelated record type be allowed? For example, if we have parent [A, B] and other C, should parent == other be valid, or should it be a type error because C is not compatible with [A, B]? If this is intentional, it would help to add a system test to lock that behavior.
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