1 files changed, 55 insertions, 0 deletions
diff --git a/tests/proc/texplicitgenerics.nim b/tests/proc/texplicitgenerics.nim
new file mode 100644
index 000000000..833d77b3b
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+++ b/tests/proc/texplicitgenerics.nim
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+block: # issue #16376
+  type
+    Matrix[T] = object
+      data: T
+  proc randMatrix[T](m, n: int, max: T): Matrix[T] = discard
+  proc randMatrix[T](m, n: int, x: Slice[T]): Matrix[T] = discard
+  template randMatrix[T](m, n: int): Matrix[T] = randMatrix[T](m, n, T(1.0))
+  let B = randMatrix[float32](20, 10)
+
+block: # different generic param counts 
+  type
+    Matrix[T] = object
+      data: T
+  proc randMatrix[T](m: T, n: T): Matrix[T] = Matrix[T](data: T(1.0))
+  proc randMatrix[T; U: not T](m: T, n: U): (Matrix[T], U) = (Matrix[T](data: T(1.0)), default(U))
+  let b = randMatrix[float32](20, 10)
+  doAssert b == Matrix[float32](data: 1.0)
+
+block: # above for templates 
+  type
+    Matrix[T] = object
+      data: T
+  template randMatrix[T](m: T, n: T): Matrix[T] = Matrix[T](data: T(1.0))
+  template randMatrix[T; U: not T](m: T, n: U): (Matrix[T], U) = (Matrix[T](data: T(1.0)), default(U))
+  let b = randMatrix[float32](20, 10)
+  doAssert b == Matrix[float32](data: 1.0)
+
+block: # sigmatch can't handle this without pre-instantiating the type:
+  # minimized from numericalnim
+  type Foo[T] = proc (x: T)
+  proc foo[T](x: T) = discard
+  proc bar[T](f: Foo[T]) = discard
+  bar[int](foo)
+
+block: # ditto but may be wrong minimization
+  # minimized from measuremancer
+  type Foo[T] = object
+  proc foo[T](): Foo[T] = Foo[T]()
+  # this is the actual issue but there are other instantiation problems
+  proc bar[T](x = foo[T]()) = discard
+  bar[int](Foo[int]())
+  bar[int]()
+  # alternative version, also causes instantiation issue
+  proc baz[T](x: typeof(foo[T]())) = discard
+  baz[int](Foo[int]())
+
+block: # issue #21346
+  type K[T] = object
+  template s[T](x: int) = doAssert T is K[K[int]]
+  proc b1(n: bool | bool) = s[K[K[int]]](3)
+  proc b2(n: bool)        = s[K[K[int]]](3)
+  template b3(n: bool)    = s[K[K[int]]](3)
+  b1(false)     # Error: cannot instantiate K; got: <T> but expected: <T>
+  b2(false)     # Builds, on its own
+  b3(false)