Documentation fix

phases/desug.mli

@@ -1,5 +1,5 @@
-(** Desugaring: split variable initialisations, prevent incorrect double
-    evaluation, and transform for-loops to while-loops. *)
+(** Desugaring: split variable initialisations, generate array dimension
+    variables, and transform for-loops to while-loops. *)
 
 (** {2 Split variable initialisations}
 
@@ -120,9 +120,9 @@ resulting in:
     The transformation described above is applied to all array definitions,
     including extern arrays. Although dimensions of extern arrays are not
     expressions (but identifiers), the transformation is necessary in order to
-    generate consistent names to be imported/exported. E.g. in [int[n] a], [n]
-    is just a name given locally to the first dimension of [a]. Therefore it is
-    transformed into:
+    generate consistent names to be imported/exported. E.g. in [extern int[n]
+    a], [n] is just a name given locally to the first dimension of [a].
+    Therefore it is transformed into:
 {v     extern int _a_0_;
     int[_a_0_] a; v}
     Also, all occurrences of [n] in the rest of the module are replaced by