まとめ

typedesc[SomeObject]を第一引数にとろう。型に対して関数が定義できる。

enumにエイリアス

enumDef.nim

type SomeEnum {.pure.} = enum
  ValA
  ValB
  ValC
type OtherEnum {.pure.} = enum
  ValA
  ValB
  ValC

template AliasA(someEnum: typedesc[SomeEnum]): SomeEnum =
  SomeEnum.ValA

assert SomeEnum.ValA == SomeEnum.AliasA
# error!
# assert SomeEnum.ValA == AliasA
# assert SomeEnum.ValA == OtherEnum.AliasA
# echo OtherEnum.AliasA
# echo AliasA

template defineAlias*(TEnum: typedesc; value, alias: untyped): untyped =
  template alias*(tEnum: typedesc[TEnum]): TEnum =
    TEnum.value

SomeEnum.defineAlias(ValB, AliasB)

assert SomeEnum.ValB == SomeEnum.AliasB

class method

type Object = object
  value: int
var `Object.staticmember`: int = 10

proc init(TObject: typedesc[Object]; value: int): Object =
  Object(value: value)
template staticmember(_: typedesc[Object]): int = `Object.staticmember`

echo repr Object.init(10)
# stdout: 10

echo Object.staticmember
# stdout: 10