[MLton-commit] r6415

[Vesa Karvonen]

Added isDegenerate.
----------------------------------------------------------------------

U   mltonlib/trunk/com/ssh/generic/unstable/detail/value/type-info.sml
U   mltonlib/trunk/com/ssh/generic/unstable/public/value/type-info.sig

----------------------------------------------------------------------

Modified: mltonlib/trunk/com/ssh/generic/unstable/detail/value/type-info.sml
===================================================================
--- mltonlib/trunk/com/ssh/generic/unstable/detail/value/type-info.sml	2008-02-23 12:32:18 UTC (rev 6414)
+++ mltonlib/trunk/com/ssh/generic/unstable/detail/value/type-info.sml	2008-02-26 11:09:20 UTC (rev 6415)
@@ -26,9 +26,12 @@
 
    open TypeInfoRep.This
 
+   fun outT (INT r) = r
    fun outS (INS r) = r
    fun outP (INP r) = r
 
+   fun isDegenerate ? = (not o #base o outT o getT) ?
+
    fun hasBaseCase  ? = (#base o outS o getS) ?
    fun numAlts      ? = (#alts o outS o getS) ?
 

Modified: mltonlib/trunk/com/ssh/generic/unstable/public/value/type-info.sig
===================================================================
--- mltonlib/trunk/com/ssh/generic/unstable/public/value/type-info.sig	2008-02-23 12:32:18 UTC (rev 6414)
+++ mltonlib/trunk/com/ssh/generic/unstable/public/value/type-info.sig	2008-02-26 11:09:20 UTC (rev 6415)
@@ -20,6 +20,14 @@
 signature TYPE_INFO = sig
    structure TypeInfoRep : OPEN_REP
 
+   (** == Complete Types == *)
+
+   val isDegenerate : ('a, 'x) TypeInfoRep.t UnPr.t
+   (**
+    * Returns true iff the type {'a} is recursive and has no non-recursive
+    * variants.  This means that values of the type cannot be created.
+    *)
+
    (** == Sums == *)
 
    val hasBaseCase : ('a, 'x) TypeInfoRep.s UnPr.t