chore: remove repeat/while macro_rules bootstrap from Init.While#13479
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This PR removes the transitional `macro_rules` for `repeat`, `while`, and `repeat ... until` from `Init.While`. After the latest stage0 update, the `@[builtin_macro]` and `@[builtin_doElem_elab]` definitions in `Lean.Elab.BuiltinDo.Repeat` are picked up directly, so the bootstrap duplicates in `Init.While` are no longer needed. `Init.While` now only provides the `Loop` type and its `ForIn` instance. This PR also adjusts `repeat`'s `ControlInfo` to match `for ... in`: its `numRegularExits` is now unconditionally `1` rather than `if info.breaks then 1 else 0`. Reporting `0` when the body has no `break` made callers treat the continuation as dead code, which broke common patterns where the continuation has a non-`Unit` result type (see discussion on #13437).
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sgraf812
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This PR fixes `inferControlInfoSeq` and `ControlInfo.sequence` to keep aggregating `breaks`/`continues`/`returnsEarly`/`reassigns` past elements whose `ControlInfo` reports `numRegularExits := 0`. Previously the analysis short-circuited at such elements, causing the inferred info to drop any `return`/`break`/`continue` that followed. The elaboration framework only skips subsequent doElems syntactically for top-level `return`/`break`/`continue` (via `elabAsSyntacticallyDeadCode`); for every other `numRegularExits == 0` case (e.g. a `match`/`if`/`try` whose branches all terminate, or a `repeat` without `break`) the elaborator keeps visiting the continuation, and the for/match elaborator then tripped its invariant check with "Early returning ... but the info said there is no early return". With this change the inferred info matches what the elaborator actually sees, which also removes the need for the `numRegularExits := 1` workaround on `repeat` introduced in #13479.
sgraf812
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This PR fixes `inferControlInfoSeq` and `ControlInfo.sequence` to keep aggregating `breaks`/`continues`/`returnsEarly`/`reassigns` past elements whose `ControlInfo` reports `numRegularExits := 0`. Previously the analysis short-circuited at such elements, causing the inferred info to drop any `return`/`break`/`continue` that followed. The elaboration framework only skips subsequent doElems syntactically for top-level `return`/`break`/`continue` (via `elabAsSyntacticallyDeadCode`); for every other `numRegularExits == 0` case (e.g. a `match`/`if`/`try` whose branches all terminate, or a `repeat` without `break`) the elaborator keeps visiting the continuation, and the for/match elaborator then tripped its invariant check with "Early returning ... but the info said there is no early return". With this change the inferred info matches what the elaborator actually sees, which also removes the need for the `numRegularExits := 1` workaround on `repeat` introduced in #13479.
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…3486) This PR fixes `inferControlInfoSeq` and `ControlInfo.sequence` to keep aggregating `breaks`/`continues`/`returnsEarly`/`reassigns` past elements whose `ControlInfo` reports `numRegularExits := 0`. Previously the analysis short-circuited at such elements, so any trailing `return`/`break`/`continue` was missing from the inferred info. The elaboration framework only skips subsequent doElems syntactically for top-level `return`/`break`/`continue`; for every other `numRegularExits == 0` case (e.g. a `match`/`if`/`try` whose branches all terminate, or a `repeat` without `break`) the elaborator keeps visiting the continuation and the for/match elaborator then tripped its invariant check with `Early returning ... but the info said there is no early return`. With this change the inferred info matches what the elaborator actually sees, which also removes the need for the `numRegularExits := 1` workaround on `repeat` introduced in #13479.
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This PR removes the transitional
macro_rulesforrepeat,while, andrepeat ... untilfromInit.While. After the latest stage0 update, the@[builtin_macro]and@[builtin_doElem_elab]definitions inLean.Elab.BuiltinDo.Repeatare picked up directly, so the bootstrap duplicates inInit.Whileare no longer needed.Init.Whilenow only provides theLooptype and itsForIninstance.This PR also adjusts
repeat'sControlInfoto matchfor ... in: itsnumRegularExitsis now unconditionally1rather thanif info.breaks then 1 else 0. Reporting0when the body has nobreakcausesinferControlInfoSeq(in any enclosing sequence whoseControlInfois inferred — e.g. a surroundingfor/if/match/trybody) to stop aggregating after therepeatand miss anyreturn/break/continuethat follows. The corresponding elaborator then sees the actual control flow disagree with the inferred info and throws errors likeEarly returning ... but the info said there is no early return. The new test intests/elab/newdo.leanpins down the regression. See #13437 for further discussion.