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Niels Lohmann
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* 📡 Document a duplicate-object-key rejection recipe RFC 8259 leaves handling of duplicate object keys to the implementation; this library silently keeps only the last value for a repeated key. Discussion #5085 asked for an opt-in rejection mode. Decision: don't change library behavior, but document the existing parser-callback workaround instead. Adds a "Recipe: rejecting duplicate object keys" section to parser_callbacks.md, adapted from a community-contributed workaround. Fixed an off-by-one bug in the original snippet: object_start reports the depth of the object's parent, while key events inside that object report depth+1, so indexing the per-depth key set with the same depth in both places caused an out-of-bounds access on nested objects. Verified the published snippet compiles and behaves correctly for flat duplicates, nested duplicates, sibling objects sharing key names, and arrays of objects. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Cross-link the duplicate-key recipe with the existing object_t behavior docs object_t.md and features/types/index.md already document that duplicate object keys resolve to an unspecified value (RFC 8259 leaves this to the implementation). The new recipe's intro overstated this as a guaranteed "last value wins" rule, which isn't true in general -- parsing text keeps the last value, but constructing from an initializer list keeps the first. Reworded the recipe to point at object_t's "unspecified" behavior instead of asserting a specific rule, and added cross-links from both existing pages to the new recipe. Signed-off-by: Niels Lohmann <mail@nlohmann.me> * Turn the duplicate-key recipe into a standalone, compiled example Replace the inline code fence in the "rejecting duplicate object keys" recipe with a proper docs/mkdocs/docs/examples/*.cpp + .output pair, included via --8<-- like every other example on the site. The .output file was generated by running it through the project's actual example build (docs/Makefile: single_include, -std=c++11, -DJSON_USE_GLOBAL_UDLS=0) and cross-checked with `make check_output`, and the source passes the pinned astyle 3.4.13 formatting unchanged. Signed-off-by: Niels Lohmann <mail@nlohmann.me> --------- Signed-off-by: Niels Lohmann <mail@nlohmann.me>
3 lines
49 B
Plaintext
3 lines
49 B
Plaintext
{"one":1,"two":2}
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duplicate JSON object key: one
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