54 lines
1.3 KiB
Plaintext
54 lines
1.3 KiB
Plaintext
|
%
|
||
|
|
% Edinburgh IO.
|
||
|
|
%
|
||
|
|
|
||
|
|
see(user) :- !, set_input(user_input).
|
||
|
|
see(F) :- var(F), !,
|
||
|
|
'$do_error'(instantiation_error,see(F)).
|
||
|
|
see(F) :- current_input(Stream),
|
||
|
|
'$user_file_name'(Stream,F).
|
||
|
|
see(F) :- current_stream(_,read,Stream), '$user_file_name'(Stream,F), !,
|
||
|
|
set_input(Stream).
|
||
|
|
see(Stream) :- '$stream'(Stream), current_stream(_,read,Stream), !,
|
||
|
|
set_input(Stream).
|
||
|
|
see(F) :- open(F,read,Stream), set_input(Stream).
|
||
|
|
|
||
|
|
seeing(File) :- current_input(Stream),
|
||
|
|
stream_property(Stream,file_name(NFile)),
|
||
|
|
(
|
||
|
|
stream_property(user_input,file_name(NFile))
|
||
|
|
->
|
||
|
|
File = user
|
||
|
|
;
|
||
|
|
NFile = File
|
||
|
|
).
|
||
|
|
|
||
|
|
seen :- current_input(Stream), close(Stream), set_input(user).
|
||
|
|
|
||
|
|
tell(user) :- !, set_output(user_output).
|
||
|
|
tell(F) :- var(F), !,
|
||
|
|
'$do_error'(instantiation_error,tell(F)).
|
||
|
|
tell(F) :-
|
||
|
|
current_output(Stream),
|
||
|
|
stream_property(Stream,file_name(F)),
|
||
|
|
!.
|
||
|
|
tell(F) :- current_stream(_,write,Stream), '$user_file_name'(Stream, F), !,
|
||
|
|
set_output(Stream).
|
||
|
|
tell(Stream) :-
|
||
|
|
'$stream'(Stream),
|
||
|
|
current_stream(_,write,Stream), !,
|
||
|
|
set_output(Stream).
|
||
|
|
tell(F) :-
|
||
|
|
open(F,write,Stream),
|
||
|
|
set_output(Stream).
|
||
|
|
|
||
|
|
telling(File) :-
|
||
|
|
current_output(Stream),
|
||
|
|
stream_property(Stream,file_name(NFile)),
|
||
|
|
( stream_property(user_output,file_name(NFile)) -> File = user ; File = NFile ).
|
||
|
|
|
||
|
|
told :- current_output(Stream),
|
||
|
|
set_output(user),
|
||
|
|
close(Stream).
|
||
|
|
|