foreach macro fix for strings

gintro/gimplgobj.nim

@@ -420,11 +420,17 @@ macro foreach*(container: gtk.Container; p: untyped; arg: typed): untyped =
   let procNameCdecl = "foreach_cdecl_" & $foreachID
   var r1s = """
 proc $1(c: ptr gtk.Widget00; p: pointer) {.cdecl.} =
-  let a = cast[$3](p) # OK for refs and maybe basic types like int, but wrong for string
+  when $3 is ref:
+    let a = cast[$3](p)
+  else:
+    let a = cast[ref $3](p)
   let h: pointer = g_object_get_qdata(c, Quark)
   assert(h != nil)
   let cn: gtk.Container = cast[gtk.Container](h)
-  $2(cn, a)
+  when $3 is ref:
+    $2(cn, a)
+  else:
+    $2(cn, a[])
 """ % [$procNameCdecl, $p, ats]
  
   let r2s ="""
@@ -433,15 +439,15 @@ proc $1(container: gtk.Container; a: $2) =
     GC_ref(a)
     gtk_container_foreach(cast[ptr gtk.Container00](container.impl), $3, cast[pointer](a))
   else:
-    var ar: ref $2 # this branch has issues, as the Nim proc p expects a value type
+    var ar: ref $2
     new(ar)
     ar[] = a
     GC_ref(ar)
     gtk_container_foreach(cast[ptr gtk.Container00](container.impl), $3, cast[pointer](ar))
 $1($5, $4)
 """ % [$procName, ats, $procNameCdecl, $arg, $container]
-  echo r1s
-  echo r2s
+  #echo r1s
+  #echo r2s
   result = parseStmt(r1s & r2s)
 
-# 447 lines
+# 453 lines