Generic types

@Type, @Input, and @Interface accept Generic[T]. Each unique parametrization is synthesized into one concrete GraphQL type at build time and memoized, so the same parametrization always resolves to the same named type.

from typing import Generic, TypeVar
from fastql import Field, Query, Schema, Type

T = TypeVar("T")


@Type
class Page(Generic[T]):
    total: int
    items: list[T]


@Type
class User:
    id: int


@Query
class Queries:
    @Field
    def users(self) -> Page[User]:
        return Page(total=1, items=[User(1)])

The example synthesizes a UserPage type whose items field is typed [User!]!. Synthetic names are derived from the parameter (User + Page → UserPage); pass a name template with a {} placeholder to override the naming scheme. TypeVar fields are resolved against the concrete parameters at each parametrization site.

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