blob: 0508a37a1594f7da45558cc8507c8c43fd64e47c (
plain) (
blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
|
import macros
{.experimental: "callOperator".}
type Foo[T: proc] = object
callback: T
macro `()`(foo: Foo, args: varargs[untyped]): untyped =
result = newCall(newDotExpr(foo, ident"callback"))
for a in args:
result.add(a)
var f1Calls = 0
var f = Foo[proc()](callback: proc() = inc f1Calls)
doAssert f1Calls == 0
f()
doAssert f1Calls == 1
var f2Calls = 0
f.callback = proc() = inc f2Calls
doAssert f2Calls == 0
f()
doAssert f2Calls == 1
let g = Foo[proc (x: int): int](callback: proc (x: int): int = x * 2 + 1)
doAssert g(15) == 31
proc `()`(args: varargs[string]): string =
result = "("
for a in args: result.add(a)
result.add(')')
let a = "1"
let b = "2"
let c = "3"
doAssert a(b) == "(12)"
doAssert a.b(c) == `()`(b, a, c)
doAssert (a.b)(c) == `()`(a.b, c)
doAssert `()`(a.b, c) == `()`(`()`(b, a), c)
|