Is it possible to "specialize" an existing procedure/template?

[Varriount]

Say I have an existing procedure like this:

proc foo(a, b, c, d: int) =
  echo a + b + c + d

Is it possible to use spread to create a version of this procedure (with the same name) that takes a body of arguments?

foo:
  a = 1
  b = 2
  c = 3
  d = 4

[metagn]

As a bare minimum:

import spread

proc fooImpl(a, b, c, d: int) =
  echo a + b + c + d

template foo(args: untyped) =
  spread(fooImpl, args)
# or, to keep regular call syntax working:
from macros import unpackVarargs
template foo(args: varargs[untyped]) =
  spread.unpackVarargs(fooImpl, args)

foo:
  a = 1
  b = 2
  c = 3
  d = 4

The limitations are that foo needs an untyped parameter due to the normally invalid a = 1 etc statements, which means it can't be passed around as a proc value; and foo and fooImpl can't have the same name i.e. overload each other, because the fooImpl overload will have a typed parameter where the untyped argument is supposed to be which will again cause it to get typechecked.

As long as these limitations are acknowledged though, a way to generate these could be nice, maybe as simple as adding {.spread.} to a proc