Merge pull request #364 from triska/master

Documentation addition, and correction of error term

src/prolog/lib/charsio.pl

@@ -60,7 +60,7 @@ extend_var_list_([V|Vs], N, VarList, NewVarList, VarType) :-
 get_single_char(C) :-
     (  var(C) -> '$get_single_char'(C)
     ;  atom_length(C, 1) -> '$get_single_char'(C)
-    ;  throw(error(domain_error(in_character, C), get_single_char/1))
+    ;  throw(error(type_error(in_character, C), get_single_char/1))
     ).
 
 

src/prolog/lib/format.pl

@@ -28,6 +28,7 @@
            if N is 0 or omitted, no decimal point is used.
      ~ND   like ~Nd, separating digits to the left of the decimal point
            in groups of three, using the character "," (comma)
+     ~|    place a tab stop at this position
      ~N|   where N is an integer: place a tab stop at text column N
      ~N+   where N is an integer: place a tab stop N characters
            after the previous tab stop (or start of line)