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Niels LohmannandGitHub
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* docs: document the complexity of ordered_map operations ordered_map stores its elements in a std::vector in insertion order and has no lookup index, so emplace, operator[], at, find, count, erase, and insert are all linear scans. The documentation stated no complexity for any operation, neither in ordered_map.md nor in ordered_json.md. Add a per-operation complexity table and note the consequence: building or parsing an ordered_json object of n keys is O(n^2). Measured with -O2 -DNDEBUG for parsing a flat object of n keys, ordered_json is 5x slower than json at n=2000 and 54x slower at n=16000, with the timings quadrupling per doubling of n. Cross-reference the table from ordered_json.md and from the object order page, which recommends ordered_json without mentioning the cost. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * docs: move the Complexity section after Member functions scripts/check_structure.py enforces a fixed section order for pages under docs/mkdocs/docs/api, in which Complexity comes after Member functions. The section had been placed right after Iterator invalidation, which made ci_test_build_documentation fail with structure/section_order. No content change beyond the move; the table columns are realigned to the narrower content. Signed-off-by: Niels Lohmann <mail@nlohmann.me> --------- Signed-off-by: Niels Lohmann <mail@nlohmann.me>