fixes #5478

compiler/semtempl.nim

@@ -144,10 +144,8 @@ proc semTemplBody(c: var TemplCtx, n: PNode): PNode
 
 proc openScope(c: var TemplCtx) =
   openScope(c.c)
-  inc c.scopeN
 
 proc closeScope(c: var TemplCtx) =
-  dec c.scopeN
   closeScope(c.c)
 
 proc semTemplBodyScope(c: var TemplCtx, n: PNode): PNode =
@@ -172,7 +170,6 @@ proc newGenSym(kind: TSymKind, n: PNode, c: var TemplCtx): PSym =
   result = newSym(kind, considerQuotedIdent(n), c.owner, n.info)
   incl(result.flags, sfGenSym)
   incl(result.flags, sfShadowed)
-  #if c.scopeN == 0: incl(result.flags, sfFromGeneric)
 
 proc addLocalDecl(c: var TemplCtx, n: var PNode, k: TSymKind) =
   # locals default to 'gensym':
@@ -275,10 +272,12 @@ proc semRoutineInTemplBody(c: var TemplCtx, n: PNode, k: TSymKind): PNode =
   for i in patternPos..miscPos:
     n.sons[i] = semTemplBody(c, n.sons[i])
   # open scope for locals
+  inc c.scopeN
   openScope(c)
   n.sons[bodyPos] = semTemplBody(c, n.sons[bodyPos])
   # close scope for locals
   closeScope(c)
+  dec c.scopeN
   # close scope for parameters
   closeScope(c)
 
@@ -346,7 +345,8 @@ proc semTemplBody(c: var TemplCtx, n: PNode): PNode =
   of nkBindStmt:
     result = semBindStmt(c.c, n, c.toBind)
   of nkMixinStmt:
-    result = semMixinStmt(c.c, n, c.toMixin)
+    if c.scopeN > 0: result = semTemplBodySons(c, n)
+    else: result = semMixinStmt(c.c, n, c.toMixin)
   of nkEmpty, nkSym..nkNilLit:
     discard
   of nkIfStmt:

tests/template/tmixin_in_proc.nim

@@ -0,0 +1,22 @@
+discard """
+  output: '''monkey'''
+"""
+# bug #5478
+template creature*(name: untyped) =
+  type
+    name*[T] = object
+      color: T
+
+  proc `init name`*[T](c: T): name[T] =
+    mixin transform
+    transform()
+
+creature(Lion)
+
+type Monkey* = object
+proc transform*() =
+  echo "monkey"
+
+var
+  m: Monkey
+  y = initLion(m)  #this one failed to compile