Avoid a quadratic walk when parsing long call chains - #4184
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parse_expression_terminator runs after every infix operator and called pm_block_call_p, which walks the whole receiver chain, even when the binding power alone already decided the result. Check the binding power first; pm_block_call_p is pure, so the condition is unchanged. Parsing "a" followed by 8000 ".b" links drops from 44.8ms to 0.46ms. Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
kddnewton
approved these changes
Jul 28, 2026
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parse_expression_terminator runs after every infix operator and called pm_block_call_p, which walks the whole receiver chain, even when the binding power alone already decided the result. Check the binding power first; pm_block_call_p is pure, so the condition is unchanged.
Parsing "a" followed by 8000 ".b" links drops from 44.8ms to 0.46ms.