I use `JsonNode` for my dynamic type, it works great for a `kwargs` standin. I
usually name it `options`, but for sake of consistency I named it `kwargs`
here. I use it all over an in-production tool at work, with permission to share:
import std/json
import std/strformat
proc get_json_value*[T: bool | float | int | string | JsonNode](node:
JsonNode,
keys:
seq[string],
default:
T): T =
var current_node = node
for key in keys:
if key in current_node:
current_node = current_node[key]
else:
return default
when T is bool:
if current_node.kind == JBool:
return current_node.get_bool
when T is float:
if current_node.kind == JFloat or current_node.kind == JInt:
return current_node.get_float
when T is int:
if current_node.kind == JInt:
return current_node.get_int
when T is string:
if current_node.kind == JString:
return current_node.get_str
when T is JsonNode:
if current_node.kind in [JObject, JArray]:
return current_node
return default
proc get_json_value*[T: bool | float | int | string | JsonNode](node:
JsonNode,
key: string,
default:
T): T =
node.get_json_value(@[key], default)
proc foo(a: int, b: string, kwargs: JsonNode = %*{}) =
echo &"Calling foo() with {kwargs=}"
let kwarg1 = kwargs.get_json_value("kwarg1", "default")
echo &"{kwarg1=}"
foo(1, "bar")
foo(2, "baz", %*{"kwarg1": "something else"})
Run
Output:
Calling foo() with kwargs={}
kwarg1=default
Calling foo() with kwargs={"kwarg1":"something else"}
kwarg1=something else
Run
