Auditing the documentation against the actual code (not against what I
remembered writing) surfaced a real, previously undocumented defect:
README.md claimed a backreference-free, unbounded-lookahead-free
pattern "runs in linear time", but that is only true of Pattern_match/
Pattern_fullmatch (one anchored attempt). Pattern_search tries every
candidate start position as an independent from-scratch attempt, so it
is quadratic in the worst case even for the simplest pattern, since
concept.md Section 7.2's engine (which shares work across start
positions in one linear pass) is not implemented yet. Measured directly
with a*b over a run of plain a's: 0.32s at n=10,000, 19.2s at n=80,000,
an ~4x slowdown per doubling. Pattern_finditer/Pattern_split/
Pattern_sub all build on the same search loop and inherit it.
README.md and docs/API.md now state this precisely, with the measured
numbers, wherever the affected functions are documented, rather than
repeating the incorrect blanket "linear time" claim. No code changed;
this is a documentation correction only.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01EjuMk8kY9SDus1wWe2K9xY
retoorandClaude Sonnet 5
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