proc free(p: pointer) {.
importc: "free", nodecl
.}

proc calloc(num, size: cuint): pointer {.
importc: "calloc", nodecl
.}

template withRef(x, y: untyped)

template `+`[T](p: ptr T; off: int): ptr T

template `[]`[T](p: ptr T; off: int): T