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73 lines
2.0 KiB
Markdown
73 lines
2.0 KiB
Markdown
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# basic_json::dump
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```cpp
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string_t dump(const int indent = -1,
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const char indent_char = ' ',
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const bool ensure_ascii = false,
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const error_handler_t error_handler = error_handler_t::strict) const
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```
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Serialization function for JSON values. The function tries to mimic
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Python's `json.dumps()` function, and currently supports its `indent`
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and `ensure_ascii` parameters.
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## Parameters
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`indent` (in)
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: If indent is nonnegative, then array elements and object
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members will be pretty-printed with that indent level. An indent level of
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`0` will only insert newlines. `-1` (the default) selects the most compact
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representation.
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`indent_char` (in)
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: The character to use for indentation if `indent` is
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greater than `0`. The default is ` ` (space).
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`ensure_ascii` (in)
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: If `ensure_ascii` is true, all non-ASCII characters
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in the output are escaped with `\uXXXX` sequences, and the result consists
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of ASCII characters only.
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`error_handler` (in)
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: how to react on decoding errors; there are three
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possible values: `strict` (throws and exception in case a decoding error
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occurs; default), `replace` (replace invalid UTF-8 sequences with U+FFFD),
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and `ignore` (ignore invalid UTF-8 sequences during serialization; all
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bytes are copied to the output unchanged).
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## Return value
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string containing the serialization of the JSON value
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## Exception safety
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Strong guarantee: if an exception is thrown, there are no
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changes to any JSON value.
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## Complexity
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Linear.
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## Notes
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Binary values are serialized as object containing two keys:
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- "bytes": an array of bytes as integers
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- "subtype": the subtype as integer or `#!json null` if the binary has no subtype
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## Example
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The following example shows the effect of different `indent`,
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`indent_char`, and `ensure_ascii` parameters to the result of the
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serialization.
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```cpp
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--8<-- "examples/dump.cpp"
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```
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Output:
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```json
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--8<-- "examples/dump.output"
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```
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