Iteratively parse nested parentheses in Pratt parser - #1509
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Replace the lookahead-based grouping parentheses counter (countGroupingParentheses) with a bottom-up iterative approach in parsePrimary() to eliminate quadratic O(N^2) lookahead scans while keeping O(1) call-stack frames on deeply nested parenthesized expressions. Also track recursion depth across iterative operator, selector, and unary chains and stop parsing immediately when the recursion limit is exceeded.
l46kok
approved these changes
Sep 24, 2026
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Replace the lookahead-based grouping parentheses counter (countGroupingParentheses) with a bottom-up iterative approach in parsePrimary() to eliminate quadratic O(N^2) lookahead scans while keeping O(1) call-stack frames on deeply nested parenthesized expressions. Also track recursion depth across iterative operator, selector, and unary chains and stop parsing immediately when the recursion limit is exceeded.