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📝 add more API documentation

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Niels Lohmann
2020-08-12 14:29:25 +02:00
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doc/mkdocs/docs/api/basic_json/value.md
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@ -12,8 +12,8 @@ ValueType value(const json_pointer& ptr,
const ValueType& default_value) const;
```
1. Returns either a copy of an object's element at the specified key `key`
or a given default value if no element with key `key` exists.
1. Returns either a copy of an object's element at the specified key `key` or a given default value if no element with
key `key` exists.
The function is basically equivalent to executing
```cpp
@ -24,8 +24,8 @@ ValueType value(const json_pointer& ptr,
}
```
2. Returns either a copy of an object's element at the specified JSON pointer `ptr`
or a given default value if no value at `ptr` exists.
2. Returns either a copy of an object's element at the specified JSON pointer `ptr` or a given default value if no value
at `ptr` exists.
The function is basically equivalent to executing
```cpp
@ -36,16 +36,14 @@ ValueType value(const json_pointer& ptr,
}
```
Unlike [`operator[]`](operator[].md), this
function does not implicitly add an element to the position defined by `key`/`ptr`
key. This function is furthermore also applicable to const objects.
Unlike [`operator[]`](operator[].md), this function does not implicitly add an element to the position defined by
`key`/`ptr` key. This function is furthermore also applicable to const objects.
## Template parameters
`ValueType`
: type compatible to JSON values, for instance `#!cpp int` for
JSON integer numbers, `#!cpp bool` for JSON booleans, or `#!cpp std::vector` types for
JSON arrays. Note the type of the expected value at `key`/`ptr` and the default
: type compatible to JSON values, for instance `#!cpp int` for JSON integer numbers, `#!cpp bool` for JSON booleans,
or `#!cpp std::vector` types for JSON arrays. Note the type of the expected value at `key`/`ptr` and the default
value `default_value` must be compatible.
## Parameters
@ -72,15 +70,15 @@ changes to any JSON value.
## Exceptions
1. The function can throw thw following exceptions:
- Throws [`type_error.302`](../../home/exceptions.md#jsonexceptiontype_error302) if `default_value` does not match the type of the
value at `key`
- Throws [`type_error.306`](../../home/exceptions.md#jsonexceptiontype_error306) if the JSON value is not an object; in that case,
using `value()` with a key makes no sense.
- Throws [`type_error.302`](../../home/exceptions.md#jsonexceptiontype_error302) if `default_value` does not match
the type of the value at `key`
- Throws [`type_error.306`](../../home/exceptions.md#jsonexceptiontype_error306) if the JSON value is not an object;
in that case, using `value()` with a key makes no sense.
2. The function can throw thw following exceptions:
- Throws [`type_error.302`](../../home/exceptions.md#jsonexceptiontype_error302) if `default_value` does not match the type of the
value at `ptr`
- Throws [`type_error.306`](../../home/exceptions.md#jsonexceptiontype_error306) if the JSON value is not an object; in that case,
using `value()` with a key makes no sense.
- Throws [`type_error.302`](../../home/exceptions.md#jsonexceptiontype_error302) if `default_value` does not match
the type of the value at `ptr`
- Throws [`type_error.306`](../../home/exceptions.md#jsonexceptiontype_error306) if the JSON value is not an object;
in that case, using `value()` with a key makes no sense.
## Complexity
@ -91,8 +89,7 @@ changes to any JSON value.
??? example
The example below shows how object elements can be queried
with a default value.
The example below shows how object elements can be queried with a default value.
```cpp
--8<-- "examples/basic_json__value.cpp"
@ -106,8 +103,7 @@ changes to any JSON value.
??? example
The example below shows how object elements can be queried
with a default value.
The example below shows how object elements can be queried with a default value.
```cpp
--8<-- "examples/basic_json__value_ptr.cpp"