8 files changed, 75 insertions, 20 deletions
diff --git a/tests/showoff/tdrdobbs_examples.nim b/tests/showoff/tdrdobbs_examples.nim
index 78f711325..c61e177dc 100644
--- a/tests/showoff/tdrdobbs_examples.nim
+++ b/tests/showoff/tdrdobbs_examples.nim
@@ -40,14 +40,14 @@ const msb3999 = mostSignificantBit(3999)
 
 echo msb3999, " ", mostSignificantBit(0), " ", square(44)
 
-proc filter[T](a: openarray[T], predicate: proc (x: T): bool): seq[T] =
+proc filter[T](a: openArray[T], predicate: proc (x: T): bool): seq[T] =
   result = @[] # @[] constructs the empty seq
   for x in a:
     if predicate(x): result.add(x)
 
-proc map[T, S](a: openarray[T], fn: proc (x: T): S): seq[S] =
+proc map[T, S](a: openArray[T], fn: proc (x: T): S): seq[S] =
   newSeq(result, a.len)
-  for i in 0 .. <a.len: result[i] = fn(a[i])
+  for i in 0 ..< a.len: result[i] = fn(a[i])
 
 
 type
@@ -105,10 +105,10 @@ proc pat2kind(pattern: string): FormulaKind =
 import macros
 
 proc matchAgainst(n, pattern: NimNode): NimNode {.compileTime.} =
-  template `@`(current, field: expr): expr =
+  template `@`(current, field: untyped): untyped =
     newDotExpr(current, newIdentNode(astToStr(field)))
 
-  template `==@`(n, pattern: expr): expr =
+  template `==@`(n, pattern: untyped): untyped =
     newCall("==", n@kind, newIdentNode($pat2kind($pattern.ident)))
 
   case pattern.kind
@@ -126,7 +126,7 @@ proc matchAgainst(n, pattern: NimNode): NimNode {.compileTime.} =
   else:
     error "invalid pattern"
 
-macro `=~` (n: Formula, pattern: expr): bool =
+macro `=~` (n: Formula, pattern: untyped): bool =
   result = matchAgainst(n, pattern)
 
 proc isPolyTerm2(n: Formula): bool = n =~ c * x^c
diff --git a/tests/showoff/tformatopt.nim b/tests/showoff/tformatopt.nim
index f33ed6921..420dd026b 100644
--- a/tests/showoff/tformatopt.nim
+++ b/tests/showoff/tformatopt.nim
@@ -10,7 +10,7 @@ import macros
 proc invalidFormatString() =
   echo "invalidFormatString"
 
-template formatImpl(handleChar: expr) =
+template formatImpl(handleChar: untyped) =
   var i = 0
   while i < f.len:
     if f[i] == '$':
@@ -29,15 +29,15 @@ template formatImpl(handleChar: expr) =
       i += 1
 
 proc `%`*(f: string, a: openArray[string]): string =
-  template identity(x: expr): expr = x
+  template identity(x: untyped): untyped = x
   result = ""
   formatImpl(identity)
 
-macro optFormat{`%`(f, a)}(f: string{lit}, a: openArray[string]): expr =
+macro optFormat{`%`(f, a)}(f: string{lit}, a: openArray[string]): untyped =
   result = newNimNode(nnkBracket)
   let f = f.strVal
   formatImpl(newLit)
-  result = nestList(!"&", result)
+  result = nestList(newIdentNode("&"), result)
 
 template optAdd1{x = y; add(x, z)}(x, y, z: string) =
   x = y & z
diff --git a/tests/showoff/tgenericmacrotypes.nim b/tests/showoff/tgenericmacrotypes.nim
new file mode 100644
index 000000000..cc07f4355
--- /dev/null
+++ b/tests/showoff/tgenericmacrotypes.nim
@@ -0,0 +1,55 @@
+# issue #7974
+
+import macros
+
+macro genTypeA(arg: typed): untyped =
+  if arg.typeKind != ntyTypeDesc:
+    error("expected typedesc", arg)
+
+  result = arg.getTypeInst[1]
+
+macro genTypeB(arg: typed): untyped =
+  if arg.typeKind != ntyTypeDesc:
+    error("expected typedesc", arg)
+
+
+  let typeSym = arg.getTypeInst[1]
+  result =
+    nnkTupleTy.newTree(
+      nnkIdentDefs.newTree(
+        ident"a", typeSym, newEmptyNode()
+      )
+    )
+
+type
+  # this is the trivial case, MyTypeA[T] is basically just T, nothing else. But it works.
+  MyTypeA[T] = genTypeA(T)
+  # in this case I generate `tuple[a: T]`. This this is something the compiler does not want
+  MyTypeB[T] = genTypeB(T)
+
+# these are just alias types for int32 and float32, nothing really happens, but it works
+var a1: MyTypeA[int32]
+doAssert a1 is MyTypeA[int32]
+doAssert a1 is int32
+a1 = 0'i32
+var a2: MyTypeA[float32]
+doAssert a2 is MyTypeA[float32]
+doAssert a2 is float32
+a2 = 0'f32
+var a3: MyTypeA[float32]
+doAssert a3 is MyTypeA[float32]
+doAssert a3 is float32
+a3 = 0'f32
+
+var b1: MyTypeB[int32]   # cannot generate VM code fur tuple[a: int32]
+doAssert b1 is MyTypeB[int32]
+doAssert b1 is tuple[a: int32]
+b1 = (a: 0'i32)
+var b2: MyTypeB[float32]
+doAssert b2 is MyTypeB[float32]
+doAssert b2 is tuple[a: float32]
+b2 = (a: 0'f32)
+var b3: MyTypeB[float32]
+doAssert b3 is MyTypeB[float32]
+doAssert b3 is tuple[a: float32]
+b3 = (a: 0'f32)
diff --git a/tests/showoff/thello2.nim b/tests/showoff/thello2.nim
index d2e2f6227..3ccb4e3be 100644
--- a/tests/showoff/thello2.nim
+++ b/tests/showoff/thello2.nim
@@ -1,5 +1,5 @@
 discard """
-  output: '''(a: 3, b: 4, s: abc)'''
+  output: '''(a: 3, b: 4, s: "abc")'''
 """
 
 type
diff --git a/tests/showoff/thtml1.nim b/tests/showoff/thtml1.nim
index c7a083c21..fe0cd3b1e 100644
--- a/tests/showoff/thtml1.nim
+++ b/tests/showoff/thtml1.nim
@@ -2,7 +2,7 @@ discard """
   output: "<br>"
 """
 
-template htmlTag(tag: expr) {.immediate.} =
+template htmlTag(tag: untyped) =
   proc tag(): string = "<" & astToStr(tag) & ">"
 
 htmlTag(br)
diff --git a/tests/showoff/thtml2.nim b/tests/showoff/thtml2.nim
index faeb4e50d..dcf6534a5 100644
--- a/tests/showoff/thtml2.nim
+++ b/tests/showoff/thtml2.nim
@@ -4,20 +4,20 @@ discard """
 
 import strutils
 
-template html(name: expr, matter: stmt) {.immediate.} =
+template html(name, matter: untyped) =
   proc name(): string =
     result = "<html>"
     matter
     result.add("</html>")
 
-template nestedTag(tag: expr) {.immediate.} =
-  template tag(matter: stmt) {.immediate.} =
+template nestedTag(tag: untyped) =
+  template tag(matter: untyped) =
     result.add("<" & astToStr(tag) & ">")
     matter
     result.add("</" & astToStr(tag) & ">")
 
-template simpleTag(tag: expr) {.immediate.} =
-  template tag(matter: expr) {.immediate.} =
+template simpleTag(tag: untyped) =
+  template tag(matter: untyped) =
     result.add("<$1>$2</$1>" % [astToStr(tag), matter])
 
 nestedTag body
diff --git a/tests/showoff/tonce.nim b/tests/showoff/tonce.nim
index 6fc372e87..ed2684dcf 100644
--- a/tests/showoff/tonce.nim
+++ b/tests/showoff/tonce.nim
@@ -5,7 +5,7 @@ new instantiation
 some call of p'''
 """
 
-template once(body: stmt) =
+template once(body) =
   var x {.global.} = false
   if not x:
     x = true
diff --git a/tests/showoff/tquasiquote.nim b/tests/showoff/tquasiquote.nim
index df7fccc33..404712a02 100644
--- a/tests/showoff/tquasiquote.nim
+++ b/tests/showoff/tquasiquote.nim
@@ -1,10 +1,10 @@
 discard """
-  outputsub: '''tquasiquote.nim(14,8): Check failed: 1 > 2'''
+  outputsub: '''tquasiquote.nim(14, 8): Check failed: 1 > 2'''
 """
 
 import macros
 
-macro check(ex: expr): stmt =
+macro check(ex: untyped): untyped =
   var info = ex.lineInfo
   var expString = ex.toStrLit
   result = quote do: