Access with default value: value¶
Overview¶
In many situations such as configuration files, missing values are not exceptional, but may be treated as if a default value was present.
Example
Consider the following JSON value:
{
"logOutput": "result.log",
"append": true
}
Assume the value is parsed to a json
variable j
.
expression | value |
---|---|
j | {"logOutput": "result.log", "append": true} |
j.value("logOutput", "logfile.log") | "result.log" |
j.value("append", true) | true |
j.value("append", false) | true |
j.value("logLevel", "verbose") | "verbose" |
Note¶
Exceptions
value
can only be used with objects. For other types, abasic_json::type_error
is thrown.