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2.8 KiB
2.8 KiB
basic_json::sax_parse
// (1)
template <typename InputType, typename SAX>
static bool sax_parse(InputType&& i,
SAX* sax,
input_format_t format = input_format_t::json,
const bool strict = true,
const bool ignore_comments = false);
// (2)
template<class IteratorType, class SAX>
static bool sax_parse(IteratorType first, IteratorType last,
SAX* sax,
input_format_t format = input_format_t::json,
const bool strict = true,
const bool ignore_comments = false);
Read from input and generate SAX events
-
Read from a compatible input.
-
Read from a pair of character iterators
The value_type of the iterator must be a integral type with size of 1, 2 or 4 bytes, which will be interpreted respectively as UTF-8, UTF-16 and UTF-32.
The SAX event lister must follow the interface of json_sax
.
Template parameters
InputType
- A compatible input, for instance:
- an
std::istream
object - a
FILE
pointer - a C-style array of characters
- a pointer to a null-terminated string of single byte characters
- an object
obj
for whichbegin(obj)
andend(obj)
produces a valid pair of iterators.
- an
IteratorType
- Description
SAX
- Description
Parameters
i
(in)- Input to parse from.
sax
(in)- SAX event listener
format
(in)- the format to parse (JSON, CBOR, MessagePack, or UBJSON) (optional,
input_format_t::json
by default), seeinput_format_t
for more information strict
(in)- whether the input has to be consumed completely (optional,
#!cpp true
by default) ignore_comments
(in)- whether comments should be ignored and treated like whitespace (
#!cpp true
) or yield a parse error (#!cpp false
); (optional,#!cpp false
by default) first
(in)- iterator to start of character range
last
(in)- iterator to end of character range
Return value
return value of the last processed SAX event
Exception safety
Complexity
Linear in the length of the input. The parser is a predictive LL(1) parser. The complexity can be higher if the SAX
consumer sax
has a super-linear complexity.
Notes
A UTF-8 byte order mark is silently ignored.
Examples
??? example
The example below demonstrates the `sax_parse()` function reading from string and processing the events with a
user-defined SAX event consumer.
```cpp
--8<-- "examples/sax_parse.cpp"
```
Output:
```json
--8<-- "examples/sax_parse.output"
```
Version history
- Added in version 3.2.0.
- Ignoring comments via
ignore_comments
added in version 3.9.0.