support for matching generic types' procs in generic concepts

tests/concepts/tmapconcept.nim

@@ -0,0 +1,102 @@
+discard """
+output: '''10
+10
+nil
+1'''
+msg: '''
+K=string V=int
+K=int64 V=string
+K=int V=int
+'''
+"""
+
+import tables, typetraits
+
+template ok(check) = assert check
+template no(check) = assert(not check)
+
+type
+  Enumerable[T] = concept e
+    for v in e:
+      v is T
+
+  Map[K, V] = concept m, var mvar
+    m[K] is V
+    mvar[K] = V
+    m.contains(K) is bool
+    m.valuesSeq is Enumerable[V]
+
+  TreeMap[K, V] = object
+    root: int
+
+  SparseSeq = object
+    data: seq[int]
+
+  JudyArray = object
+    data: SparseSeq
+
+static:
+  ok seq[int] is Enumerable[int]
+  ok seq[string] is Enumerable
+  ok seq[int] is Enumerable[SomeNumber]
+  ok SparseSeq.data is Enumerable
+  no seq[string] is Enumerable[int]
+  no int is Enumerable
+  no int is Enumerable[int]
+
+# Complete the map concept implementation for the Table type
+proc valuesSeq[K, V](t: Table[K, V]): seq[V]  =
+  result = @[]
+  for k, v in t:
+    result.add v
+
+# Map concept inplementation for TreeMap
+proc valuesSeq(t: TreeMap): array[1, TreeMap.V] =
+  var v: t.V
+  result = [v]
+
+proc contains[K, V](t: TreeMap[K, V], key: K): bool = true
+
+proc `[]=`[K, V](t: var TreeMap[K, V], key: K, val: V) = discard
+proc `[]`(t: TreeMap, key: t.K): TreeMap.V = discard
+
+# Map concept implementation for the non-generic JudyArray
+proc valuesSeq(j: JudyArray): SparseSeq = j.data
+
+proc contains(t: JudyArray, key: int): bool = true
+
+proc `[]=`(t: var JudyArray, key, val: int) = discard
+proc `[]`(t: JudyArray, key: int): int = discard
+
+iterator items(s: SparseSeq): int =
+  for i in s.data: yield i
+
+# Generic proc defined over map
+proc getFirstValue[K,V](m : Map[K,V]): V =
+  static: echo "K=", K.name, " V=", V.name
+
+  for i in m.valuesSeq:
+    return i
+
+  raise newException(RangeError, "no values")
+
+proc useConceptProcInGeneric[K, V](t: Table[K, V]): V =
+  return t.getFirstValue
+
+var t = initTable[string, int]()
+t["test"] = 10
+
+echo t.getFirstValue
+echo t.useConceptProcInGeneric
+
+var tm = TreeMap[int64, string](root: 0)
+echo getFirstValue(tm)
+
+var j = JudyArray(data: SparseSeq(data: @[1, 2, 3]))
+echo getFirstValue(j)
+
+static:
+  ok Table[int, float] is Map
+  ok Table[int, string] is Map[SomeNumber, string]
+  no JudyArray is Map[string, int]
+