implemented 'pure' enums

compiler/semtypes.nim

@@ -38,6 +38,7 @@ proc semEnum(c: PContext, n: PNode, prev: PType): PType =
       localError(n.sons[0].info, errInheritanceOnlyWithEnums)
     counter = lastOrd(base) + 1
   rawAddSon(result, base)
+  let isPure = result.sym != nil and sfPure in result.sym.flags
   for i in countup(1, sonsLen(n) - 1): 
     case n.sons[i].kind
     of nkEnumFieldDef: 
@@ -73,12 +74,12 @@ proc semEnum(c: PContext, n: PNode, prev: PType): PType =
     else: illFormedAst(n)
     e.typ = result
     e.position = int(counter)
-    if result.sym != nil and sfExported in result.sym.flags: 
+    if result.sym != nil and sfExported in result.sym.flags:
-      incl(e.flags, sfUsed)   # BUGFIX
+      incl(e.flags, sfUsed)
-      incl(e.flags, sfExported) # BUGFIX
+      incl(e.flags, sfExported)
-      StrTableAdd(c.module.tab, e) # BUGFIX
+      if not isPure: StrTableAdd(c.module.tab, e)
     addSon(result.n, newSymNode(e))
-    if sfGenSym notin e.flags: addDeclAt(c, e, c.tab.tos - 1)
+    if sfGenSym notin e.flags and not isPure: addDeclAt(c, e, c.tab.tos - 1)
     inc(counter)
 
 proc semSet(c: PContext, n: PNode, prev: PType): PType = 

doc/manual.txt

@@ -795,6 +795,19 @@ values to use:
 As can be seen from the example, it is possible to both specify a field's 
 ordinal value and its string value by using a tuple. It is also
 possible to only specify one of them.
+
+An enum can be marked with the ``pure`` pragma so that it's fields are not
+added to the current scope, so they always need to be accessed 
+via ``TMyEnum.value``:
+
+.. code-block:: nimrod
+
+  type
+    TMyEnum {.pure.} = enum
+      valueA, valueB, valueC, valueD
+  
+  echo valueA # error: Unknown identifier
+  echo TMyEnum.valueA # works
 
 
 String type

todo.txt

@@ -45,6 +45,8 @@ version 0.9.XX
 
 - JS gen:
   - fix exception handling
+- object branch transitions can't work with the current 'reset'; add a 'reset'
+  with an additional parameter
 - fix remaining closure bugs:
   - test evals.nim with closures
   - what about macros with closures?