Working test cases for the sophisticated matrix library example from the manual

Fixed the dot operator when used within return types (see tgenericdotrettype)
Fixed the matching of generic concepts aliases used with the implicit generics style

compiler/semexprs.nim

@@ -911,8 +911,7 @@ proc makeDeref(n: PNode): PNode =
     t = skipTypes(baseTyp, {tyGenericInst, tyAlias})
 
 const
-  tyTypeParamsHolders = {tyGenericInst, tyCompositeTypeClass,
+  tyTypeParamsHolders = {tyGenericInst, tyCompositeTypeClass}
-                         tyUserTypeClass, tyUserTypeClassInst}
   tyDotOpTransparent = {tyVar, tyPtr, tyRef, tyAlias}
 
 proc readTypeParameter(c: PContext, typ: PType,
@@ -1107,6 +1106,23 @@ proc builtinFieldAccess(c: PContext, n: PNode, flags: TExprFlags): PNode =
   var ty = n.sons[0].typ
   var f: PSym = nil
   result = nil
+
+  template tryReadingGenericParam(t: PType) =
+    case t.kind
+    of tyTypeParamsHolders:
+      return readTypeParameter(c, t, i, n.info)
+    of tyUserTypeClasses:
+      if t.isResolvedUserTypeClass:
+        return readTypeParameter(c, t, i, n.info)
+      else:
+        n.typ = makeTypeFromExpr(c, copyTree(n))
+        return n
+    of tyGenericParam:
+      n.typ = makeTypeFromExpr(c, copyTree(n))
+      return n
+    else:
+      discard
+
   if isTypeExpr(n.sons[0]) or (ty.kind == tyTypeDesc and ty.base.kind != tyNone):
     if ty.kind == tyTypeDesc: ty = ty.base
     ty = ty.skipTypes(tyDotOpTransparent)
@@ -1124,8 +1140,6 @@ proc builtinFieldAccess(c: PContext, n: PNode, flags: TExprFlags): PNode =
         markUsed(n.info, f, c.graph.usageSym)
         styleCheckUse(n.info, f)
         return
-    of tyTypeParamsHolders:
-      return readTypeParameter(c, ty, i, n.info)
     of tyObject, tyTuple:
       if ty.n != nil and ty.n.kind == nkRecList:
         let field = lookupInRecord(ty.n, i)
@@ -1134,8 +1148,7 @@ proc builtinFieldAccess(c: PContext, n: PNode, flags: TExprFlags): PNode =
           n.typ.n = copyTree(n)
           return n
     else:
-      # echo "TYPE FIELD ACCESS"
+      tryReadingGenericParam(ty)
-      # debug ty
       return
     # XXX: This is probably not relevant any more
     # reset to prevent 'nil' bug: see "tests/reject/tenumitems.nim":
@@ -1178,8 +1191,7 @@ proc builtinFieldAccess(c: PContext, n: PNode, flags: TExprFlags): PNode =
   # we didn't find any field, let's look for a generic param
   if result == nil:
     let t = n.sons[0].typ.skipTypes(tyDotOpTransparent)
-    if t.kind in tyTypeParamsHolders:
+    tryReadingGenericParam(t)
-      result = readTypeParameter(c, t, i, n.info)
 
 proc dotTransformation(c: PContext, n: PNode): PNode =
   if isSymChoice(n.sons[1]):

compiler/semtypes.nim

@@ -845,9 +845,9 @@ proc liftParamType(c: PContext, procKind: TSymKind, genericParams: PNode,
 
     for i in 0 .. paramType.sonsLen - 2:
       if paramType.sons[i].kind == tyStatic:
-        var x = copyNode(ast.emptyNode)
+        var staticCopy = paramType.sons[i].exactReplica
-        x.typ = paramType.sons[i]
+        staticCopy.flags.incl tfInferrableStatic
-        result.rawAddSon makeTypeFromExpr(c, x) # aka 'tyUnknown'
+        result.rawAddSon staticCopy
       else:
         result.rawAddSon newTypeS(tyAnything, c)
 
@@ -891,7 +891,7 @@ proc liftParamType(c: PContext, procKind: TSymKind, genericParams: PNode,
                                           allowMetaTypes = true)
       result = liftingWalk(expanded, true)
 
-  of tyUserTypeClass, tyBuiltInTypeClass, tyAnd, tyOr, tyNot:
+  of tyUserTypeClasses, tyBuiltInTypeClass, tyAnd, tyOr, tyNot:
     result = addImplicitGeneric(copyType(paramType, getCurrOwner(c), true))
 
   of tyGenericParam:
@@ -1357,6 +1357,8 @@ proc semTypeNode(c: PContext, n: PNode, prev: PType): PType =
     else: result = semGeneric(c, n, s, prev)
   of nkDotExpr:
     let typeExpr = semExpr(c, n)
+    if typeExpr.typ.kind == tyFromExpr:
+      return typeExpr.typ
     if typeExpr.typ.kind != tyTypeDesc:
       localError(n.info, errTypeExpected)
       result = errorType(c)

compiler/semtypinst.nim

@@ -404,6 +404,8 @@ proc replaceTypeVarsTAux(cl: var TReplTypeVars, t: PType): PType =
   case t.kind
   of tyGenericInvocation:
     result = handleGenericInvocation(cl, t)
+    if result.lastSon.kind == tyUserTypeClass:
+      result.kind = tyUserTypeClassInst
 
   of tyGenericBody:
     localError(cl.info, errCannotInstantiateX, typeToString(t))

compiler/sigmatch.nim

@@ -613,6 +613,13 @@ proc matchUserTypeClass*(c: PContext, m: var TCandidate,
       template paramSym(kind): untyped =
         newSym(kind, typeParamName, Concept.sym, Concept.sym.info)
 
+      block addTypeParam:
+        for prev in typeParams:
+          if prev[1].id == typ.id:
+            param = paramSym prev[0].kind
+            param.typ = prev[0].typ
+            break addTypeParam
+
         case typ.kind
         of tyStatic:
           param = paramSym skConst
@@ -631,9 +638,10 @@ proc matchUserTypeClass*(c: PContext, m: var TCandidate,
                       else:
                         makeTypeDesc(c, typ)
 
-      addDecl(c, param)
         typeParams.safeAdd((param, typ))
       
+      addDecl(c, param)
+
   for param in Concept.n[0]:
     var
       dummyName: PNode
@@ -696,7 +704,7 @@ proc matchUserTypeClass*(c: PContext, m: var TCandidate,
     put(m.bindings, p[1], p[0].typ)
 
   if ff.kind == tyUserTypeClassInst:
-    result = generateTypeInstance(c, m.bindings, ff.sym.info, ff)
+    result = generateTypeInstance(c, m.bindings, Concept.sym.info, ff)
   else:
     result = copyType(ff, ff.owner, true)
 

compiler/types.nim

@@ -183,7 +183,7 @@ proc iterOverTypeAux(marker: var IntSet, t: PType, iter: TTypeIter,
   if result: return
   if not containsOrIncl(marker, t.id):
     case t.kind
-    of tyGenericInst, tyGenericBody, tyAlias:
+    of tyGenericInst, tyGenericBody, tyAlias, tyInferred:
       result = iterOverTypeAux(marker, lastSon(t), iter, closure)
     else:
       for i in countup(0, sonsLen(t) - 1):
@@ -1320,6 +1320,9 @@ proc computeSizeAux(typ: PType, a: var BiggestInt): BiggestInt =
     if result < 0: return
     if a < maxAlign: a = maxAlign
     result = align(result, a)
+  of tyInferred:
+    if typ.len > 1:
+      result = computeSizeAux(typ.lastSon, a)
   of tyGenericInst, tyDistinct, tyGenericBody, tyAlias:
     result = computeSizeAux(lastSon(typ), a)
   of tyTypeClasses:
@@ -1351,17 +1354,16 @@ proc getSize(typ: PType): BiggestInt =
   if result < 0: internalError("getSize: " & $typ.kind)
 
 proc containsGenericTypeIter(t: PType, closure: RootRef): bool =
-  if t.kind == tyStatic:
+  case t.kind
+  of tyStatic:
     return t.n == nil
-
+  of tyTypeDesc:
-  if t.kind == tyTypeDesc:
     if t.base.kind == tyNone: return true
     if containsGenericTypeIter(t.base, closure): return true
     return false
-
+  of GenericTypes + tyTypeClasses + {tyFromExpr}:
-  if t.kind in GenericTypes + tyTypeClasses + {tyFromExpr}:
     return true
-
+  else:
     return false
 
 proc containsGenericType*(t: PType): bool =

compiler/vmgen.nim

@@ -1678,7 +1678,8 @@ proc gen(c: PCtx; n: PNode; dest: var TDest; flags: TGenFlags = {}) =
       elif sfImportc in s.flags: c.importcSym(n.info, s)
       genLit(c, n, dest)
     of skConst:
-      gen(c, s.ast, dest)
+      let constVal = if s.ast != nil: s.ast else: s.typ.n
+      gen(c, constVal, dest)
     of skEnumField:
       if dest < 0: dest = c.getTemp(n.typ)
       if s.position >= low(int16) and s.position <= high(int16):

doc/manual/generics.txt

@@ -305,6 +305,9 @@ The concept types can be parametric just like the regular generic types:
 
 .. code-block:: nim
   ### matrixalgo.nim
+  
+  import typetraits
+
   type
     AnyMatrix*[R, C: static[int]; T] = concept m, var mvar, type M
       M.ValueType is T
@@ -314,9 +317,13 @@ The concept types can be parametric just like the regular generic types:
       m[int, int] is T
       mvar[int, int] = T
 
+      type TransposedType = StripGenericParams(M)[C, R, T]
+
     AnySquareMatrix*[N: static[int], T] = AnyMatrix[N, N, T]
 
-  proc transpose*[R, C, T](m: AnyMatrix[R, C, T]): m.type.basis[C, R, T] =
+    AnyTransform3D* = AnyMatrix[4, 4, float]
+
+  proc transposed*(m: AnyMatrix): m.TransposedType =
     for r in 0 .. <m.R:
       for c in 0 .. <m.C:
         result[r, c] = m[c, r]
@@ -324,6 +331,9 @@ The concept types can be parametric just like the regular generic types:
   proc determinant*(m: AnySquareMatrix): int =
     ...
 
+  proc setPerspectiveProjection*(m: AnyTransform3D) =
+    ...
+
   --------------
   ### matrix.nim
 
@@ -331,11 +341,11 @@ The concept types can be parametric just like the regular generic types:
     Matrix*[M, N: static[int]; T] = object
       data: array[M*N, T]
 
-  proc `[]`*(m: Matrix; m, n: int): m.T =
+  proc `[]`*(M: Matrix; m, n: int): M.T =
-    m.data[m * m.N + n]
+    M.data[m * M.N + n]
 
-  proc `[]=`*(m: var Matrix; m, n: int; v: m.T) =
+  proc `[]=`*(M: var Matrix; m, n: int; v: M.T) =
-    m.data[m * m.N + n] = v
+    M.data[m * M.N + n] = v
 
   # Adapt the Matrix type to the concept's requirements
   template Rows*(M: type Matrix): expr = M.M
@@ -347,8 +357,12 @@ The concept types can be parametric just like the regular generic types:
 
   import matrix, matrixalgo
 
-  var v: Matrix[3, 3, int]
+  var
-  echo v.determinant
+    m: Matrix[3, 3, int]
+    projectionMatrix: Matrix[4, 4, float]
+
+  echo m.transposed.determinant
+  setPerspectiveProjection projectionMatrix
 
 When the concept type is matched against a concrete type, the unbound type
 parameters are inferred from the body of the concept in a way that closely

tests/concepts/matrix.nim

@@ -0,0 +1,15 @@
+type
+  Matrix*[M, N: static[int]; T] = object
+    data: array[M*N, T]
+
+proc `[]`*(M: Matrix; m, n: int): M.T =
+  M.data[m * M.N + n]
+
+proc `[]=`*(M: var Matrix; m, n: int; v: M.T) =
+  M.data[m * M.N + n] = v
+
+# Adapt the Matrix type to the concept's requirements
+template Rows*(M: type Matrix): expr = M.M
+template Cols*(M: type Matrix): expr = M.N
+template ValueType*(M: type Matrix): typedesc = M.T
+

tests/concepts/matrixalgo.nim

@@ -0,0 +1,28 @@
+import typetraits
+
+type
+  AnyMatrix*[R, C: static[int]; T] = concept m, var mvar, type M
+    M.ValueType is T
+    M.Rows == R
+    M.Cols == C
+
+    m[int, int] is T
+    mvar[int, int] = T
+
+    type TransposedType = StripGenericParams(M)[C, R, T]
+
+  AnySquareMatrix*[N: static[int], T] = AnyMatrix[N, N, T]
+
+  AnyTransform3D* = AnyMatrix[4, 4, float]
+
+proc transposed*(m: AnyMatrix): m.TransposedType =
+  for r in 0 .. <m.R:
+    for c in 0 .. <m.C:
+      result[r, c] = m[c, r]
+
+proc determinant*(m: AnySquareMatrix): int =
+  return 0
+
+proc setPerspectiveProjection*(m: AnyTransform3D) =
+  discard
+

tests/concepts/tmatrixconcept.nim

@@ -1,7 +1,8 @@
 discard """
-output: "0\n0"
+output: "0\n0\n0"
 msg: '''
 R=3 C=3 TE=9 FF=14 FC=20 T=int
+R=3 C=3 T=int
 '''
 """
 
@@ -41,13 +42,25 @@ proc `[]=`(m: var MyMatrix; r, c: int, v: m.T) =
 
 proc foo(x: MyMatrix, arr: array[15, x.T]) = discard
 
-proc matrixProc[R, C, TE, FF, FC, T](m: Matrix[R, C, TE, FF, FC, T]): T =
+proc genericMatrixProc[R, C, TE, FF, FC, T](m: Matrix[R, C, TE, FF, FC, T]): T =
   static:
     echo "R=", R, " C=", C, " TE=", TE, " FF=", FF, " FC=", FC, " T=", T.name
   
   m[0, 0]
 
-proc myMatrixProc(x: MyMatrix): MyMatrix.T = matrixProc(x)
+proc implicitMatrixProc(m: Matrix): m.T =
+  static:
+    echo "R=", m.Rows,
+        " C=", m.Cols,
+        # XXX: fix these
+        #" TE=", m.TotalElements,
+        #" FF=", m.FromFoo,
+        #" FC=", m.FromConst,
+        " T=", m.T.name
+    
+  m[0, 0]
+
+proc myMatrixProc(x: MyMatrix): MyMatrix.T = genericMatrixProc(x)
 
 var x: MyMatrix[3, 3, int]
 
@@ -63,5 +76,6 @@ static:
   no x is Matrix[3, 4, 9, 15, 20, int]
 
 echo x.myMatrixProc
-echo x.matrixProc
+echo x.genericMatrixProc
+echo x.implicitMatrixProc
 

tests/concepts/tmatrixlib.nim

@@ -0,0 +1,31 @@
+discard """
+output: "0"
+"""
+
+import matrix, matrixalgo
+
+import typetraits # XXX: this should be removed
+
+var m: Matrix[3, 3, int]
+var projectionMatrix: Matrix[4, 4, float]
+
+echo m.transposed.determinant
+setPerspectiveProjection projectionMatrix
+
+template ok(x) = assert x
+template no(x) = assert(not x)
+
+static:
+  ok projectionMatrix is AnyTransform3D
+  no m is AnyTransform3D
+  
+  type SquareStringMatrix = Matrix[5, 5, string]
+  
+  ok SquareStringMatrix is AnyMatrix
+  ok SquareStringMatrix is AnySquareMatrix
+  no SquareStringMatrix is AnyTransform3D
+  
+  ok Matrix[5, 10, int] is AnyMatrix
+  no Matrix[7, 15, float] is AnySquareMatrix
+  no Matrix[4, 4, int] is AnyTransform3D
+

tests/generics/tgenericdotrettype.nim

@@ -0,0 +1,29 @@
+discard """
+output: '''string
+int
+(int, string)
+'''
+"""
+
+import typetraits
+
+type
+  Foo[T, U] = object
+    x: T
+    y: U
+
+proc bar[T](a: T): T.U =
+  echo result.type.name
+
+proc bas(x: auto): x.T =
+  echo result.type.name
+
+proc baz(x: Foo): (Foo.T, x.U) =
+  echo result.type.name
+
+var
+  f: Foo[int, string]
+  x = bar f
+  z = bas f
+  y = baz f
+