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51 lines
1.9 KiB
Markdown
51 lines
1.9 KiB
Markdown
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# basic_json::string_t
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```cpp
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using string_t = StringType;
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```
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The type used to store JSON strings.
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[RFC 8259](https://tools.ietf.org/html/rfc8259) describes JSON strings as follows:
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> A string is a sequence of zero or more Unicode characters.
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To store objects in C++, a type is defined by the template parameter described below. Unicode values are split by the
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JSON class into byte-sized characters during deserialization.
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## Template parameters
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`StringType`
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: the container to store strings (e.g., `std::string`). Note this container is used for keys/names in objects, see
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[object_t](object_t.md).
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## Notes
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#### Default type
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With the default values for `StringType` (`std::string`), the default value for `string_t` is `#!cpp std::string`.
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#### Encoding
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Strings are stored in UTF-8 encoding. Therefore, functions like `std::string::size()` or `std::string::length()` return
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the number of bytes in the string rather than the number of characters or glyphs.
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#### String comparison
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[RFC 8259](https://tools.ietf.org/html/rfc8259) states:
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> Software implementations are typically required to test names of object members for equality. Implementations that
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> transform the textual representation into sequences of Unicode code units and then perform the comparison numerically,
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> code unit by code unit, are interoperable in the sense that implementations will agree in all cases on equality or
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> inequality of two strings. For example, implementations that compare strings with escaped characters unconverted may
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> incorrectly find that `"a\\b"` and `"a\u005Cb"` are not equal.
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This implementation is interoperable as it does compare strings code unit by code unit.
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#### Storage
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String values are stored as pointers in a `basic_json` type. That is, for any access to string values, a pointer of type
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`string_t*` must be dereferenced.
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## Version history
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- Added in version 1.0.0.
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