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Pull request overview
This PR addresses a semantic typing issue around tuple constructors when the expected tuple element types are view types (var/lent), which could lead to incorrect typing and downstream failures (notably for (lent T, lent T) scenarios referenced in #24723).
Changes:
- Update
changeTypeto avoid rewriting tuple-constructor element node types when the target element type isvar/lent. - Add a regression test ensuring tuple yields requiring
lentelements still correctly error when an element has no address.
Reviewed changes
Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.
| File | Description |
|---|---|
| tests/lent/tlent_tuple_address.nim | Adds a regression test for tuple yields with lent elements that should fail due to an unaddressable expression. |
| compiler/semexprs.nim | Prevents changeType from force-typing tuple elements to var/lent, avoiding incorrect view-typing of non-addressable expressions. |
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Thanks for your hard work on this PR! Hint: mm: orc; opt: speed; options: -d:release |
narimiran
pushed a commit
that referenced
this pull request
May 8, 2026
ref #25783 This pull request addresses an issue with addressability of tuple elements of type `lent` or `var` in Nim, ensuring that expressions involving these types are handled correctly during type changes. The main changes introduce a check to prevent attempting to change the type of tuple elements that are views (`var` or `lent`), and a new test is added to verify the correct error is raised when trying to take the address of such elements. Type system and semantic analysis improvements: * Added the `isViewTarget` template in `semexprs.nim` to check if a type is a view (`var` or `lent`), and updated `changeType` to skip type changes for tuple elements that are views. This prevents invalid addressability operations on these types. [[1]](diffhunk://#diff-539da3a63df08fa987f1b0c67d26cdc690753843d110b6bf0805a685eeaffd40R655-R657) [[2]](diffhunk://#diff-539da3a63df08fa987f1b0c67d26cdc690753843d110b6bf0805a685eeaffd40R686-R693) Testing: * Added a new test `tlent_tuple_address.nim` to verify that attempting to take the address of tuple elements of type `lent` correctly produces an "expression has no address" error. (cherry picked from commit f2e4ae0)
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ref #25783
This pull request addresses an issue with addressability of tuple elements of type
lentorvarin Nim, ensuring that expressions involving these types are handled correctly during type changes. The main changes introduce a check to prevent attempting to change the type of tuple elements that are views (varorlent), and a new test is added to verify the correct error is raised when trying to take the address of such elements.Type system and semantic analysis improvements:
isViewTargettemplate insemexprs.nimto check if a type is a view (varorlent), and updatedchangeTypeto skip type changes for tuple elements that are views. This prevents invalid addressability operations on these types. [1] [2]Testing:
tlent_tuple_address.nimto verify that attempting to take the address of tuple elements of typelentcorrectly produces an "expression has no address" error.