Fixes implicit and explicit generics in procedures (#18808)

* Fixes implicit and explicit generics

* moved block logic into 'maybeInstantiateGeneric'

* Added more tests

* Update compiler/semexprs.nim

Co-authored-by: Andreas Rumpf <rumpf_a@web.de>

tests/generics/timplicit_and_explicit.nim

@@ -0,0 +1,45 @@
+
+block: # basic test
+  proc doStuff[T](a: SomeInteger): T = discard
+  proc doStuff[T;Y](a: SomeInteger, b: Y): Y = discard
+  assert typeof(doStuff[int](100)) is int
+  assert typeof(doStuff[int](100, 1.0)) is float
+  assert typeof(doStuff[int](100, "Hello")) is string
+
+  proc t[T](x: T; z: int | float): seq[T] = result.add(x & $z)
+
+  assert t[string]("Hallo", 2.0) == @["Hallo" & $2.0]
+
+  proc t2[T](z: int | float): seq[T] = result.add($z)
+
+  assert t2[string](2.0) == @[$2.0]
+
+block: # template test
+  template someThing[T;Y](a: SomeFloat, b: SomeOrdinal): (T, Y) = (a, b)
+  assert typeof(someThing[float64, int](1.0, 100)) is (float64, int)
+
+block: # static test
+  proc t[T](s: static bool) = discard
+  proc t2[T](s: static string) = discard
+  t[string](true)
+  t2[int]("hello")
+  t2[string]("world")
+  t2[float]("test222222")
+
+block: #11152
+  proc f[T](X: typedesc) = discard
+  f[int](string)
+
+block: #15622
+  proc test1[T](a: T, b: static[string] = "") = discard
+  test1[int64](123)
+  proc test2[T](a: T, b: static[string] = "") = discard
+  test2[int64, static[string]](123)
+
+block: #4688
+  proc convertTo[T](v: int or float): T = (T)(v)
+  discard convertTo[float](1)
+
+block: #4164
+  proc printStr[T](s: static[string]): T = discard
+  discard printStr[int]("hello static")