Not sure what you mean:
import macros
macro model(name: string, body: untyped): untyped =
echo "name: ", name
echo "body: ", body.repr
result = newStmtList()
model "Person":
field Name(string):
max_length = 128
field Age(int):
unsigned validate Age > 20
Output:
name: Person
body:
field Name(string),
max_length = 128
field Age(int),
unsigned validate Age > 20
