parseJSON

bool parseJSON(out  var value,  const(char)[]  input,  out  JsonError err,
       JsonPolicy policy =  JsonPolicy.init)

@safe

Parse JSON text into a var value.

This is the primary parsing function that builds a DOM-style tree representation of the JSON data.

Parameters

`value`	Output parameter for the parsed value.
`input`	JSON text to parse.
`err`	Output parameter for error information on failure.
`policy`	Policy controlling parser behavior.

Returns

true on success, false on error (with err set).

Examples

import ddn.data.json : parseJSON, JsonError;
import ddn.var : var;

JsonError err;
var v;
if (parseJSON(v, `{"name": "John", "age": 30}`, err)) {
   assert(v["name"].as!string == "John");
   assert(v["age"].as!long == 30);
}

fnvar parseJSON(const(char)[] input) @safe

Convenience overload that parses JSON and returns the value directly.

Returns var.init on parse failure.

Parameters

input JSON text to parse.

Returns

The parsed var value, or var.init on error.

bool parseJSON(out  var value,  const(char)[]  input,  JsonReviver reviver,  out  JsonError err,
       JsonPolicy policy =  JsonPolicy.init)

@safe

Parse JSON text and apply reviver to each value.

The reviver is called in post-order traversal (children are transformed before their parents). This matches the behavior of JavaScript's JSON.parse(text, reviver).

Parameters

`value`	Output parameter for the parsed and transformed value.
`input`	JSON text to parse.
`reviver`	Delegate to transform each value. May be null (no transformation).
`err`	Output parameter for error information on failure.
`policy`	Policy controlling parser behavior.

Returns

true on success; false with err populated on parse failure.

Examples

import ddn.data.json : parseJSON, JsonReviver, JsonError;
import ddn.var : var;

// Double all integer values
JsonReviver rev = (const string key, var value) @safe {
  if (value.type == var.Type.LONG) {
     return var(value.as!long * 2);
  }
  return value;
};

JsonError err;
var v;
assert(parseJSON(v, `{"a":1,"b":2}`, rev, err));
assert(v["a"].as!long == 2);
assert(v["b"].as!long == 4);