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63 lines
1.8 KiB
Markdown
63 lines
1.8 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 7159](http://rfc7159.net/rfc7159) 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
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described below. Unicode values are split by the JSON class into
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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`).
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Note this container is used for keys/names in objects, see [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
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value for `string_t` is:
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```cpp
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std::string
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```
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#### Encoding
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Strings are stored in UTF-8 encoding. Therefore, functions like
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`std::string::size()` or `std::string::length()` return the number of
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bytes in the string rather than the number of characters or glyphs.
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#### String comparison
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[RFC 7159](http://rfc7159.net/rfc7159) states:
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> Software implementations are typically required to test names of object
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> members for equality. Implementations that transform the textual
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> representation into sequences of Unicode code units and then perform the
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> comparison numerically, code unit by code unit, are interoperable in the
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> sense that implementations will agree in all cases on equality or
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> inequality of two strings. For example, implementations that compare
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> strings with escaped characters unconverted may incorrectly find that
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> `"a\\b"` and `"a\u005Cb"` are not equal.
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This implementation is interoperable as it does compare strings code unit
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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,
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for any access to string values, a pointer of type `string_t*` must be
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dereferenced.
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## Version history
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- Added in version 1.0.0.
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