nim-lang

Field identifiers inside a nim tuple

according to the manual which mentions @ Tuple or object scope ... To the end of the tuple/object definition, I though it's possible to access field elements of an array or tuple inside the corresponding data type like in C where int a[]={10, a[0] + 10} is possible?

How can I create an array or tuple like var a = (x: 10, y: x + 10), because actually the parser quits with undeclared identifier x?

Do I need RTII for this kind of access?

Thanks in advance, Marcello

Solution

  • Don't think that's possible in nim, but you could use a template to get around:

    template makeTuple(input: untyped): untyped =
  (x: input, y: input + 10)

template plus10(input: untyped): untyped =
  (x: input, y: input + 10)

var a = makeTuple(2)
echo a
var b = 3.5.plus10
echo b

    This will output:

    (x: 2, y: 12)
(x: 3.5, y: 13.5)