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
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
|
discard """
nimout: '''
seq[int]
CustomSeq[int]
'''
"""
import macros, typetraits, sequtils
block: # issue #7737 original
type
CustomSeq[T] = object
data: seq[T]
proc getSubType(T: NimNode): NimNode =
echo getTypeInst(T).repr
result = getTypeInst(T)[1]
macro typed_helper(x: varargs[typed]): untyped =
let foo = getSubType(x[0])
result = quote do: discard
macro untyped_heavylifting(x: varargs[untyped]): untyped =
var containers = nnkArgList.newTree()
for arg in x:
case arg.kind:
of nnkInfix:
if eqIdent(arg[0], "in"):
containers.add arg[2]
else:
discard
result = quote do:
typed_helper(`containers`)
var a, b, c: seq[int]
untyped_heavylifting z in c, x in a, y in b:
discard
## The following gives me CustomSeq instead
## of CustomSeq[int] in getTypeInst
var u, v, w: CustomSeq[int]
untyped_heavylifting z in u, x in v, y in w:
discard
block: # issue #7737 comment
type
CustomSeq[T] = object
data: seq[T]
# when using just one argument, `foo` and `bar` should be exactly
# identical.
macro foo(arg: typed): string =
result = newLit(arg.getTypeInst.repr)
macro bar(args: varargs[typed]): untyped =
result = newTree(nnkBracket)
for arg in args:
result.add newLit(arg.getTypeInst.repr)
var
a: seq[int]
b: CustomSeq[int]
doAssert foo(a) == "seq[int]"
doAssert bar(a) == ["seq[int]"]
doAssert foo(b) == "CustomSeq[int]"
doAssert bar(b) == ["CustomSeq[int]"]
|
