Freeze shell/write errors

[chuckhoupt]

Some unexpected errors when manipulating frozen variables in the shell. I suspect the shell or write aren't expecting unbound/int/list items in frozen goals.

?- freeze(X,X), X=freeze(Y,Y).

Error: Instantiation error.
- Goal:          Error: Instantiation error.
- Goal:          builtins:functor(_A,_B,_C)
- Throw pattern: error(instantiation_error,[builtins:functor(_A,_B,_C)])
$ echo $?
2

?- freeze(Y, Z), write(Y).
Error: Instantiation error.
- Goal:          builtins:functor(_A,_B,_C)
- Throw pattern: error(instantiation_error,[builtins:functor(_A,_B,_C)])

?- freeze(Y, 1).

Error: Argument of type integer expected instead of 1.
- Error Attribute: [sio:
                     put_atom(
                         stream_descriptor('\003',open,console,
                             'standard output',[noinput|output],false,-2,0,0,
                             0,0,true,0,wt_opts(78,400,flat),[],wait,text,
                             eof_code,true,0),
                         1)]
- Throw pattern: error(type_error(integer,1),[[sio: *]])
Y->

?- freeze(Y, "a").

Error: Argument of type integer expected instead of 97.
- Error Attribute: [sio:
                     put_atom(
                         stream_descriptor('\004',open,console,
                             'standard output',[noinput|output],false,-2,0,0,
                             0,0,true,0,wt_opts(78,400,flat),[],wait,text,
                             eof_code,true,0),
                         97)]
- Throw pattern: error(type_error(integer,97),[[sio: *]])
Y->[?- 

[kenbowen]

Don’t have a full pix yet, but freeze(Y, 1) is a bug in the machinery for display of delay vars. The machinery is in blt_frez.pro, a combo of show_delay_binding/4 and w_d_t/4, the bug occurring in the latter. (I’ve also turned up a bug in put_number/3 too; see at end) w_d_t (for write_delay_term), is called from show_delay_binding/4: w_d_t(VarDelayTerm, Stream, XVPairs, Subsids) It is just a big branch on the type of Term. It has an incorrect clause: w_d_t(Term, Stream, _, []) :- atomic(Term), !, put_atom(Stream, Term). The error ?- freeze(Y, 1). Error: Argument of type integer expected instead of 1. - Error Attribute: [sio: put_atom( stream_descriptor('\003',open,console, 'standard output',[noinput|output],false,-2,0,0, 0,0,true,0,wt_opts(78,400,flat),[],wait,text, eof_code,true,0), 1)] - Throw pattern: error(type_error(integer,1),[[sio: *]]) Y-> is being thrown from the call to put_atom/2 above. Add this clause before the “atomic” clause above: w_d_t(Term, Stream, _, []) :- pbi_write(top_w_d_t_5(Term)),pbi_nl,pbi_ttyflush, integer(Term), !, put_number(Stream, long, Term). This produces: ?- freeze(Y, 1). Y-> It should yield: ?- freeze(Y, 1). Y->1 There’s a reasonable chance that the three other problems you got are similar issues in w_d_t & friends.

…

---------- The behavior showing Y-> instead of Y->1 is due to bugs in put_number/3. In sio.pro, just before the defn of put_number/3, the comment says: * OutputType may take on the following values: * byte * short * long * float * double But: ?- put_number(user,short,2). yes. ?- put_number(user,long,2). yes. ?- put_number(user,float,2.0). yes. ?- put_number(user,double,2.0). yes. So there’s a bug in put_number/3, which is essentially sio_put_number(Stream,OutputType,Number). However, I also think there’s a short-coming, in that there should be a builtin put_number/2, like this: put_number(Stream,Number) :- get_number_type(Number, OutputType), put_number(Stream,OutputType,Number). We shouldn’t have to add separate cases (integer,float,….) for simply outputting different types of numbers. Cheers, ——Ken

On Oct 12, 2019, at 6:37 PM, Chuck Houpt ***@***.***> wrote: freeze(Y, 1).