Fix infinite loops in parser and support nested IF#25
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associate-1 merged 1 commit intomainfrom Feb 19, 2026
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The parser would enter infinite loops (consuming memory until OOM) when encountering: (1) nested/replicated IF within an IF block, and (2) unknown type declarations inside variant receive CASE blocks. Both caused by parsing loops that failed to advance the token position on unrecognized constructs. Fix nested IF by detecting IF tokens as choices in parseIfStatement and recursively parsing them, storing in a new IfChoice.NestedIf field. Codegen flattens non-replicated nested IFs and emits replicated ones as loops with a _ifmatched flag. Add progress guards to all parser loops (IF, CASE, ALT, variant receive) as a safety net. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
dboreham
approved these changes
Feb 19, 2026
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Summary
IFwithinIFblocks causedparseExpressionto fail without advancing the cursor, and (2) unknown type declarations in variant? CASEblocks caused the same stall pattern.IF(choices inlined into parent chain) and replicatedIF i = 0 FOR n(emitted as a loop with_ifmatchedflag). This is a common occam idiom for searching arrays.IF,CASE,ALT, variant receive) as a safety net against future infinite loop regressions.Test plan
go test ./...).occfiles terminate without hanging (previously 4 of 9 caused OOM)🤖 Generated with Claude Code