Niels Lohmann aaf63cbff6 docs: state that NaN ordering inside containers depends on the standard ...

When the element-wise comparison of arrays or objects reaches a NaN and
a number (or another NaN) before any other difference, the result
depends on the language standard. Before C++20 the pair counts as
equivalent and the following elements (or the sizes) decide, so
[1] <= [NaN] is true. Since C++20 the comparison is unordered and
<, <=, >, >= all yield false. Document this on operator<, <=, >, >=
and <=>.

Signed-off-by: Niels Lohmann <mail@nlohmann.me>

2026-11-11 19:22:54 +01:00

..

~basic_json.md

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accept.md

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array_t.md

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array.md

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as_base_class.md

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at.md

Strong exception guarantee for operator[](json_pointer) (#5940)

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back.md

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basic_json.md

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begin.md

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binary_t.md

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binary.md

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bjdata_version_t.md

Read BJData ND-arrays of float16, restrict ND-array char to 0..127, correct BJData docs (#5931)

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boolean_t.md

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cbegin.md

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cbor_tag_handler_t.md

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cend.md

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clear.md

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contains.md

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count.md

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crbegin.md

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crend.md

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default_object_comparator_t.md

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diff.md

docs: explain signed zero in the diff() round-trip exceptions (#5944)

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dump.md

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emplace_back.md

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emplace.md

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empty.md

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end_pos.md

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end.md

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erase.md

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error_handler_t.md

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exception.md

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find.md

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flatten.md

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format_as.md

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from_bjdata.md

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from_bon8.md

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from_bson.md

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from_cbor.md

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from_msgpack.md

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from_ubjson.md

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front.md

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get_allocator.md

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get_binary.md

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get_ptr.md

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get_ref.md

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get_to.md

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get.md

json_view: get<T>() of a boolean throws for the exact number types, as basic_json does (#5992)

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index.md

Split the json_view feature page into sub-pages (#6018)

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input_format_t.md

docs: new design for the documentation site (#5934)

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insert.md

insert(): strong guarantee for single elements, basic guarantee for the rest (#5996)

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invalid_iterator.md

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is_array.md

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is_binary.md

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is_boolean.md

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is_discarded.md

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is_null.md

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is_number_float.md

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is_number_integer.md

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is_number_unsigned.md

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is_number.md

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is_object.md

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is_primitive.md

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is_string.md

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is_structured.md

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items.md

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json_base_class_t.md

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json_serializer.md

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max_size.md

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merge_diff.md

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merge_patch.md

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meta.md

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number_float_t.md

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number_integer_t.md

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number_unsigned_t.md

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object_comparator_t.md

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object_t.md

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object.md

📝 add more docs (#5231)

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operator_eq.md

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operator_ge.md

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operator_gt.md

docs: state that NaN ordering inside containers depends on the standard

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operator_le.md

docs: state that NaN ordering inside containers depends on the standard

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operator_lt.md

docs: state that NaN ordering inside containers depends on the standard

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operator_ne.md

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operator_spaceship.md

docs: state that NaN ordering inside containers depends on the standard

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operator_value_t.md

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operator_ValueType.md

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operator[].md

Strong exception guarantee for operator[](json_pointer) (#5940)

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operator+=.md

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operator=.md

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other_error.md

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out_of_range.md

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parse_error.md

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parse_event_t.md

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parse.md

Split the json_view feature page into sub-pages (#6018)

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parser_callback_t.md

Document the contract of object keys passed to json_sax::key and key callbacks (#5956)

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patch_inplace.md

Docs: reading and writing files; patch_inplace() is not atomic (#6017)

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patch.md

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push_back.md

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rbegin.md

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rend.md

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sax_parse.md

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size.md

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start_pos.md

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std_formatter.md

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std_hash.md

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std_swap.md

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string_t.md

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swap.md

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to_bjdata.md

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to_bon8.md

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to_bson.md

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to_cbor.md

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to_msgpack.md

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to_string.md

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to_ubjson.md

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type_error.md

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type_name.md

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type.md

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unflatten.md

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update.md

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value_t.md

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value.md

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with_t.md

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