diff --git a/compiler/ast.nim b/compiler/ast.nim
index bb015ea274..bb06e7163d 100644
--- a/compiler/ast.nim
+++ b/compiler/ast.nim
@@ -626,6 +626,7 @@ type
     case kind*: TSymKind
     of skType:
       typeInstCache*: seq[PType]
+      typScope*: PScope
     of routineKinds:
       procInstCache*: seq[PInstantiation]
       scope*: PScope          # the scope where the proc was defined
@@ -799,9 +800,9 @@ const
     # imported via 'importc: "fullname"' and no format string.
 
 # creator procs:
-proc NewSym*(symKind: TSymKind, Name: PIdent, owner: PSym,
+proc newSym*(symKind: TSymKind, Name: PIdent, owner: PSym,
              info: TLineInfo): PSym
-proc NewType*(kind: TTypeKind, owner: PSym): PType
+proc newType*(kind: TTypeKind, owner: PSym): PType
 proc newNode*(kind: TNodeKind): PNode
 proc newIntNode*(kind: TNodeKind, intVal: BiggestInt): PNode
 proc newIntTypeNode*(kind: TNodeKind, intVal: BiggestInt, typ: PType): PNode
@@ -1111,7 +1112,7 @@ proc copySym(s: PSym, keepId: bool = false): PSym =
   result.loc = s.loc
   result.annex = s.annex      # BUGFIX
   
-proc NewSym(symKind: TSymKind, Name: PIdent, owner: PSym,
+proc newSym(symKind: TSymKind, Name: PIdent, owner: PSym,
             info: TLineInfo): PSym = 
   # generates a symbol and initializes the hash field too
   new(result)
diff --git a/compiler/evals.nim b/compiler/evals.nim
index 3f09664a79..35954cceca 100644
--- a/compiler/evals.nim
+++ b/compiler/evals.nim
@@ -904,18 +904,16 @@ proc evalParseStmt(c: PEvalContext, n: PNode): PNode =
                        code.info.line.int)
   #result.typ = newType(tyStmt, c.module)
  
-proc evalTypeTrait*(n: PNode, context: PSym): PNode =
-  ## XXX: This should be pretty much guaranteed to be true
-  # by the type traits procs' signatures, but until the
-  # code is more mature it doesn't hurt to be extra safe
-  internalAssert n.sons.len >= 2 and n.sons[1].kind == nkSym
+proc evalTypeTrait*(trait, operand: PNode, context: PSym): PNode =
+  InternalAssert operand.kind == nkSym and
+                 operand.sym.typ.kind == tyTypeDesc
 
-  let typ = n.sons[1].sym.typ.skipTypes({tyTypeDesc})
-  case n.sons[0].sym.name.s.normalize
+  let typ = operand.sym.typ.skipTypes({tyTypeDesc})
+  case trait.sym.name.s.normalize
   of "name":
-    result = newStrNode(nkStrLit, typ.typeToString(preferExported))
+    result = newStrNode(nkStrLit, typ.typeToString(preferName))
     result.typ = newType(tyString, context)
-    result.info = n.info
+    result.info = trait.info
   else:
     internalAssert false
 
@@ -1037,8 +1035,8 @@ proc evalMagicOrCall(c: PEvalContext, n: PNode): PNode =
   of mParseStmtToAst: result = evalParseStmt(c, n)
   of mExpandToAst: result = evalExpandToAst(c, n)
   of mTypeTrait:
-    n.sons[1] = evalAux(c, n.sons[1], {})
-    result = evalTypeTrait(n, c.module)
+    let operand = evalAux(c, n.sons[1], {})
+    result = evalTypeTrait(n[0], operand, c.module)
   of mIs:
     n.sons[1] = evalAux(c, n.sons[1], {})
     result = evalIsOp(n)
diff --git a/compiler/options.nim b/compiler/options.nim
index 5f173d240c..cfda15f6a1 100644
--- a/compiler/options.nim
+++ b/compiler/options.nim
@@ -156,6 +156,8 @@ var
 
 const oKeepVariableNames* = true
 
+const oUseLateInstantiation* = true
+
 proc mainCommandArg*: string =
   ## This is intended for commands like check or parse
   ## which will work on the main project file unless
diff --git a/compiler/semfold.nim b/compiler/semfold.nim
index 77ecf2e979..ed7b146849 100644
--- a/compiler/semfold.nim
+++ b/compiler/semfold.nim
@@ -558,9 +558,10 @@ proc getConstExpr(m: PSym, n: PNode): PNode =
   case n.kind
   of nkSym: 
     var s = n.sym
-    if s.kind == skEnumField: 
+    case s.kind
+    of skEnumField:
       result = newIntNodeT(s.position, n)
-    elif s.kind == skConst: 
+    of skConst:
       case s.magic
       of mIsMainModule: result = newIntNodeT(ord(sfMainModule in m.flags), n)
       of mCompileDate: result = newStrNodeT(times.getDateStr(), n)
@@ -578,10 +579,17 @@ proc getConstExpr(m: PSym, n: PNode): PNode =
       of mNegInf: result = newFloatNodeT(NegInf, n)
       else:
         if sfFakeConst notin s.flags: result = copyTree(s.ast)
-    elif s.kind in {skProc, skMethod}: # BUGFIX
+    of {skProc, skMethod}:
       result = n
-    elif s.kind in {skType, skGenericParam}:
+    of skType:
       result = newSymNodeTypeDesc(s, n.info)
+    of skGenericParam:
+      if s.typ.kind == tyExpr:
+        result = s.typ.n
+        result.typ = s.typ.sons[0]
+      else:
+        result = newSymNodeTypeDesc(s, n.info)
+    else: nil
   of nkCharLit..nkNilLit: 
     result = copyNode(n)
   of nkIfExpr: 
diff --git a/compiler/seminst.nim b/compiler/seminst.nim
index 601072833d..0cf5086a8d 100644
--- a/compiler/seminst.nim
+++ b/compiler/seminst.nim
@@ -130,13 +130,50 @@ proc sideEffectsCheck(c: PContext, s: PSym) =
       s.ast.sons[genericParamsPos].kind == nkEmpty:
     c.threadEntries.add(s)
 
+proc lateInstantiateGeneric(c: PContext, invocation: PType, info: TLineInfo): PType =
+  InternalAssert invocation.kind == tyGenericInvokation
+  
+  let cacheHit = searchInstTypes(invocation)
+  if cacheHit != nil:
+    result = cacheHit
+  else:
+    let s = invocation.sons[0].sym
+    let oldScope = c.currentScope
+    c.currentScope = s.typScope
+    openScope(c)
+    pushInfoContext(info)
+    for i in 0 .. <s.typ.n.sons.len:
+      let genericParam = s.typ.n[i].sym
+      let symKind = if genericParam.typ.kind == tyExpr: skConst
+                    else: skType
+
+      var boundSym = newSym(symKind, s.typ.n[i].sym.name, s, info)
+      boundSym.typ = invocation.sons[i+1].skipTypes({tyExpr})
+      boundSym.ast = invocation.sons[i+1].n
+      addDecl(c, boundSym)
+    # XXX: copyTree would have been unnecessary here if semTypeNode
+    # didn't modify its input parameters. Currently, it does modify
+    # at least the record lists of the passed object and tuple types
+    var instantiated = semTypeNode(c, copyTree(s.ast[2]), nil)
+    popInfoContext()
+    closeScope(c)
+    c.currentScope = oldScope
+    if instantiated != nil:
+      result = invocation
+      result.kind = tyGenericInst
+      result.sons.add instantiated
+      cacheTypeInst result
+
 proc instGenericContainer(c: PContext, info: TLineInfo, header: PType): PType =
-  var cl: TReplTypeVars
-  InitIdTable(cl.symMap)
-  InitIdTable(cl.typeMap)
-  cl.info = info
-  cl.c = c
-  result = ReplaceTypeVarsT(cl, header)
+  when oUseLateInstantiation:
+    lateInstantiateGeneric(c, header, info)
+  else:
+    var cl: TReplTypeVars
+    InitIdTable(cl.symMap)
+    InitIdTable(cl.typeMap)
+    cl.info = info
+    cl.c = c
+    result = ReplaceTypeVarsT(cl, header)
 
 proc instGenericContainer(c: PContext, n: PNode, header: PType): PType =
   result = instGenericContainer(c, n.info, header)
diff --git a/compiler/semmagic.nim b/compiler/semmagic.nim
index 41c379133d..b9ef8b008a 100644
--- a/compiler/semmagic.nim
+++ b/compiler/semmagic.nim
@@ -40,7 +40,7 @@ proc semTypeTraits(c: PContext, n: PNode): PNode =
     (typArg.kind == skParam and typArg.typ.sonsLen > 0):
     # This is either a type known to sem or a typedesc
     # param to a regular proc (again, known at instantiation)
-    result = evalTypeTrait(n, GetCurrOwner())
+    result = evalTypeTrait(n[0], n[1], GetCurrOwner())
   else:
     # a typedesc variable, pass unmodified to evals
     result = n
diff --git a/compiler/semstmts.nim b/compiler/semstmts.nim
index 33c0adac1d..a15b3e10a6 100644
--- a/compiler/semstmts.nim
+++ b/compiler/semstmts.nim
@@ -729,12 +729,16 @@ proc typeSectionRightSidePass(c: PContext, n: PNode) =
       # like: mydata.seq
       rawAddSon(s.typ, newTypeS(tyEmpty, c))
       s.ast = a
-      inc c.InGenericContext
-      var body = semTypeNode(c, a.sons[2], nil)
-      dec c.InGenericContext
-      if body != nil:
-        body.sym = s
-        body.size = -1 # could not be computed properly
+      when oUseLateInstantiation:
+        var body: PType = nil
+        s.typScope = c.currentScope.parent
+      else:
+        inc c.InGenericContext
+        var body = semTypeNode(c, a.sons[2], nil)
+        dec c.InGenericContext
+        if body != nil:
+          body.sym = s
+          body.size = -1 # could not be computed properly
       s.typ.sons[sonsLen(s.typ) - 1] = body
       popOwner()
       closeScope(c)
diff --git a/compiler/semtypes.nim b/compiler/semtypes.nim
index 8ae23f851d..1f7574bb5f 100644
--- a/compiler/semtypes.nim
+++ b/compiler/semtypes.nim
@@ -156,7 +156,7 @@ proc semRangeAux(c: PContext, n: PNode, prev: PType): PType =
     LocalError(n.Info, errRangeIsEmpty)
   var a = semConstExpr(c, n[1])
   var b = semConstExpr(c, n[2])
-  if not sameType(a.typ, b.typ): 
+  if not sameType(a.typ, b.typ):
     LocalError(n.info, errPureTypeMismatch)
   elif a.typ.kind notin {tyInt..tyInt64,tyEnum,tyBool,tyChar,
                          tyFloat..tyFloat128,tyUInt8..tyUInt32}:
@@ -204,8 +204,8 @@ proc semArray(c: PContext, n: PNode, prev: PType): PType =
         indx = e.typ.skipTypes({tyTypeDesc})
     addSonSkipIntLit(result, indx)
     if indx.kind == tyGenericInst: indx = lastSon(indx)
-    if indx.kind != tyGenericParam: 
-      if not isOrdinalType(indx): 
+    if indx.kind != tyGenericParam:
+      if not isOrdinalType(indx):
         LocalError(n.sons[1].info, errOrdinalTypeExpected)
       elif enumHasHoles(indx): 
         LocalError(n.sons[1].info, errEnumXHasHoles, indx.sym.name.s)
@@ -846,7 +846,10 @@ proc semGeneric(c: PContext, n: PNode, s: PSym, prev: PType): PType =
         LocalError(n.info, errCannotInstantiateX, s.name.s)
         result = newOrPrevType(tyError, prev, c)
       else:
-        result = instGenericContainer(c, n, result)
+        when oUseLateInstantiation:
+          result = lateInstantiateGeneric(c, result, n.info)
+        else:
+          result = instGenericContainer(c, n, result)
 
 proc semTypeExpr(c: PContext, n: PNode): PType =
   var n = semExprWithType(c, n, {efDetermineType})
diff --git a/compiler/semtypinst.nim b/compiler/semtypinst.nim
index 31fbc33e1e..5482d5df8f 100644
--- a/compiler/semtypinst.nim
+++ b/compiler/semtypinst.nim
@@ -31,7 +31,7 @@ proc checkConstructedType*(info: TLineInfo, typ: PType) =
       if t.sons[0].kind != tyObject or tfFinal in t.sons[0].flags: 
         localError(info, errInheritanceOnlyWithNonFinalObjects)
 
-proc searchInstTypes(key: PType): PType =
+proc searchInstTypes*(key: PType): PType =
   let genericTyp = key.sons[0]
   InternalAssert genericTyp.kind == tyGenericBody and
                  key.sons[0] == genericTyp and
@@ -55,7 +55,7 @@ proc searchInstTypes(key: PType): PType =
       
       return inst
 
-proc cacheTypeInst(inst: PType) =
+proc cacheTypeInst*(inst: PType) =
   # XXX: add to module's generics
   #      update the refcount
   let genericTyp = inst.sons[0]
diff --git a/compiler/sigmatch.nim b/compiler/sigmatch.nim
index 626d16d64a..fa87f27a7b 100644
--- a/compiler/sigmatch.nim
+++ b/compiler/sigmatch.nim
@@ -654,7 +654,7 @@ proc typeRel(c: var TCandidate, f, a: PType): TTypeRelation =
       result = typeRel(c, x, a) # check if it fits
   of tyTypeDesc:
     var prev = PType(idTableGet(c.bindings, f))
-    if prev == nil:
+    if prev == nil or true:
       if a.kind == tyTypeDesc:
         if f.sonsLen == 0:
           result = isGeneric
@@ -768,6 +768,7 @@ proc ParamTypesMatchAux(c: PContext, m: var TCandidate, f, a: PType,
         if evaluated != nil:
           r = isGeneric
           arg.typ = newTypeS(tyExpr, c)
+          arg.typ.sons = @[evaluated.typ]
           arg.typ.n = evaluated
         
     if r == isGeneric:
diff --git a/tests/compile/tgenericshardcases.nim b/tests/compile/tgenericshardcases.nim
new file mode 100644
index 0000000000..90981c7014
--- /dev/null
+++ b/tests/compile/tgenericshardcases.nim
@@ -0,0 +1,30 @@
+discard """
+  file: "tgenericshardcases.nim"
+  output: "int\nfloat\nint\nstring"
+"""
+
+import typetraits
+
+proc typeNameLen(x: typedesc): int {.compileTime.} =
+  result = x.name.len
+  
+macro selectType(a, b: typedesc): typedesc =
+  result = a
+
+type
+  Foo[T] = object
+    data1: array[high(T), int]
+    data2: array[1..typeNameLen(T), selectType(float, string)]
+
+  MyEnum = enum A, B, C,D
+
+var f1: Foo[MyEnum]
+var f2: Foo[int8]
+
+static:
+  assert high(f1.data1) == D
+  assert high(f1.data2) == 6 # length of MyEnum
+
+  assert high(f2.data1) == 127
+  assert high(f2.data2) == 4 # length of int8
+
diff --git a/tests/run/tmacrogenerics.nim b/tests/run/tmacrogenerics.nim
new file mode 100644
index 0000000000..5ae59e0da4
--- /dev/null
+++ b/tests/run/tmacrogenerics.nim
@@ -0,0 +1,39 @@
+discard """
+  file: "tmacrogenerics.nim"
+  msg: '''
+instantiation 1 with int and float
+instantiation 2 with float and string
+instantiation 3 with string and string
+counter: 3
+'''
+  output: "int\nfloat\nint\nstring"
+"""
+
+import typetraits, macros
+
+var counter {.compileTime.} = 0
+
+macro makeBar(A, B: typedesc): typedesc =
+  inc counter
+  echo "instantiation ", counter, " with ", A.name, " and ", B.name
+  result = A
+
+type 
+  Bar[T, U] = makeBar(T, U)
+
+var bb1: Bar[int, float]
+var bb2: Bar[float, string]
+var bb3: Bar[int, float]
+var bb4: Bar[string, string]
+
+proc match(a: int)    = echo "int"
+proc match(a: string) = echo "string"
+proc match(a: float)  = echo "float"
+
+match(bb1)
+match(bb2)
+match(bb3)
+match(bb4)
+
+static:
+  echo "counter: ", counter