Bug fixing and fixed using stored variables

polymani.pl

@@ -37,16 +37,15 @@
                  *              NLP             *
                  *******************************/
 
-debug_print(false).
-
 %% polyplay() is det
 %
 %  Interactive prompt for the NLP Interface
 %
 polyplay :-
+    %% Replace the prompt and save the old one
     prompt(OldPrompt, '> '),
+    %% Read a line as codes, from the 'user_input' stream
     read_line_to_codes(user_input, InCodes),
-    %% read_string(user_input, "\n", "\r\t ", _, In),
     prompt(_, OldPrompt),
     split_string(InCodes, " ", "\r\t", LS),
     maplist(name, LA, LS),
@@ -64,13 +63,21 @@ polyplay :-
                 writeln(NC)
             ;
                 (
-                    debug_print(true),
-                    write(LA),
-                    nl,
-                    write(TIn),
+                    NC \== [],
+                    write("Syntax error in token: "),
+                    cons(H, _, NC),
+                    write(H),
                     nl
                 ;
-                    process_input(TIn)
+                    (
+                        debug_print(true),
+                        write(LA),
+                        nl,
+                        write(TIn),
+                        nl
+                    ;
+                        process_input(TIn)
+                    )
                 )
             )
         ;
@@ -80,6 +87,9 @@ polyplay :-
     ),
     !.
 
+%% Flag which determines whether to print the parsed input or to process it
+debug_print(false).
+
 process_input(command(CL, void)) :-
     do_process_input(CL).
 process_input(command(CL, TCR)) :-
@@ -92,12 +102,16 @@ process_input(command(CL, TCR)) :-
 
 do_process_input(show_stored_polynomials) :-
     findall(nm(X,Y), polynomial_store(X,Y), D),
-    nlp_print_memory(D).
+    print_all_stored_variables(D).
 do_process_input(show(store(P), T)) :-
+    ( polynomial_store(P, _),
+      retractall(polynomial_store(P, _)); true ),
+    !,
     assertz(polynomial_store(P, T)),
     write(P),
     write(" = "),
-    print_polynomial_tree(T),
+    polynomial_tree_to_polynomial(T, Pl),
+    write(Pl),
     nl.
 do_process_input(show(load(P), void)) :-
     P \== void,
@@ -105,7 +119,8 @@ do_process_input(show(load(P), void)) :-
         polynomial_store(P, T),
         write(P),
         write(" = "),
-        print_polynomial_tree(T),
+        polynomial_tree_to_polynomial(T, Pl),
+        write(Pl),
         nl
     ;
         write("Variable not stored"),
@@ -113,14 +128,17 @@ do_process_input(show(load(P), void)) :-
     ).
 do_process_input(show(P, T)) :-
     P \== void,
+    P \== store(_),
     T \== void,
     write(P),
     write(" = "),
-    print_polynomial_tree(T),
+    polynomial_tree_to_polynomial(T, Pl),
+    write(Pl),
     nl.
 do_process_input(show(void, T)) :-
     T \== void,
-    print_polynomial_tree(T),
+    polynomial_tree_to_polynomial(T, Pl),
+    write(Pl),
     nl.
 do_process_input(store(P, T)) :-
     assertz(polynomial_store(P, T)).
@@ -139,14 +157,19 @@ do_process_input(multiply(TN, PT)) :-
     write(SP),
     nl.
 
-print_polynomial_tree(op(Op, TL, TR)) :-
-    !,
-    write(TL),
-    write(Op),
-    TR \== void,
-    print_polynomial_tree(TR).
-print_polynomial_tree(T) :-
-    write(T).
+
+%% print_all_stored_variables
+%
+%  Prints the stored variables
+%
+print_all_stored_variables([nm(X,T) | TS]) :-
+    write(X),
+    write(" = "),
+    polynomial_tree_to_polynomial(T, P),
+    write(P),
+    nl,
+    print_all_stored_variables(TS).
+print_all_stored_variables([]).
 
 polynomial_tree_to_polynomial(op(Op, TL, TR), P) :-
     !,
@@ -157,6 +180,9 @@ polynomial_tree_to_polynomial(op(Op, TL, TR), P) :-
     atom_concat(TermL, Op, Temp),
     atom_concat(Temp, TermR, PA),
     term_to_atom(P, PA).
+polynomial_tree_to_polynomial(load(P), Pl) :-
+    polynomial_store(P, TP),
+    polynomial_tree_to_polynomial(TP, Pl).
 polynomial_tree_to_polynomial(T, T).
 %% Tests:
 %% ?- polynomial_tree_to_polynomial(op(+, 2, op(+, 2, op(*, 1, y))), S).
@@ -321,6 +347,7 @@ parse_operation(*) --> [times].
 
 parse_polynomial_operand(T) --> parse_number(T).
 parse_polynomial_operand(T) --> parse_power(T).
+parse_polynomial_operand(load(T)) --> parse_stored_variable(T), { ! }.
 
 :- dynamic polynomial_store/2.
 
@@ -355,9 +382,6 @@ parse_polynomial(T, NC, NC) :-
 parse_polynomial(T) -->
     parse_polynomial_explicit(_-_, T),
     !.
-parse_polynomial(T) -->
-    parse_stored_variable(T),
-    !.
 %% Tests:
 %% ?- parse_polynomial(T, [], _).
 %@ false.
@@ -425,7 +449,7 @@ parse_command(show(store(P), T)) -->
     parse_polynomial(T),
     [as],
     parse_stored_variable(P).
-parse_command(show(load(P), void)) -->
+parse_command(show(P, void)) -->
     [show],
     parse_stored_variable(P).
 parse_command(show(void, T)) -->
@@ -475,17 +499,6 @@ parse_input(command(TC, void)) -->
 %% ?- parse_input(CT, [show, 3], _).
 %@ CT = command(show(void, 3), void).
 
-%% nlp_print_memory
-%
-%  Prints the NLP memory
-%
-nlp_print_memory([nm(X,Y)|T]) :-
-    write(X),
-    write(" = "),
-    print_polynomial_tree(Y),
-    nl,
-    nlp_print_memory(T).
-nlp_print_memory([]).
 
                  /*******************************
                  *             UI               *