set domain_error exception & use format/3 with setup_call_cleanup/3 for stream writing
write_csv/3
]).
+:- use_module(library(format)).
:- use_module(library(dcgs)).
+:- use_module(library(iso_ext)).
:- use_module(library(lists)).
option(W, O) :-
( member(W, O) -> true
- ; throw(error(unknown_opt_error(W, O), option/2)).
+ ; throw(error(domain_error(csv_option, W), option/2))).
option_extends([], Opt, Opt).
@@ -92,51 +94,54 @@ ensure_escaped([X | Y], Field) :-
escaped_field([X | Y], Field).
-write_field(Field, Opt) :-
+write_field(Out, Field, Opt) :-
( Field \== [] ->
ensure_escaped(Field, Field0),
- write(Field0)
+ format(Out, "~w", [Field0])
; option(null_value(Null_Value), Opt),
( Null_Value == empty -> true
- ; write(Null_Value))).
+ ; format(Out, "~w", [Null_Value]))).
-write_row([Field], Opt) :-
- write_field(Field, Opt).
-write_row([Field, X | Y], Opt) :-
- write_field(Field, Opt),
+write_row(Out, [Field], Opt) :-
+ write_field(Out, Field, Opt).
+write_row(Out, [Field, X | Y], Opt) :-
+ write_field(Out, Field, Opt),
option(token_separator(Tk_Sep), Opt),
- write(Tk_Sep),
- write_row([X | Y], Opt).
+ format(Out, "~w", [Tk_Sep]),
+ write_row(Out, [X | Y], Opt).
-write_rows([Row], Opt) :-
- write_row(Row, Opt).
-write_rows([Row, X | Y], Opt) :-
+write_rows(Out, [Row], Opt) :-
+ write_row(Out, Row, Opt).
+write_rows(Out, [Row, X | Y], Opt) :-
option(line_separator(Line_Sep), Opt),
- write_row(Row, Opt),
- write(Line_Sep),
- write_rows([X | Y], Opt).
+ write_row(Out, Row, Opt),
+ format(Out, "~w", [Line_Sep]),
+ write_rows(Out, [X | Y], Opt).
-write_csv(File_Name, frame(Header, Rows), Opt) :-
+write_csv_(Out, frame(Header, Rows), Opt) :-
+ option(with_header(With_Header), Opt),
+ ( With_Header == true ->
+ write_row(Out, Header, Opt),
+ option(line_separator(Line_Sep), Opt),
+ format(Out, "~w", [Line_Sep])
+ ; true),
+ write_rows(Out, Rows, Opt).
+
+
+write_csv(File_Name, Frm, Opt) :-
option_extends(Opt, [
null_value(empty),
token_separator(','),
with_header(true),
line_separator('\n')
], Opt0),
+ setup_call_cleanup(
open(File_Name, write, Out),
- set_output(Out),
- option(with_header(With_Header), Opt0),
- ( With_Header == true ->
- write_row(Header, Opt0),
- option(line_separator(Line_Sep), Opt0),
- write(Line_Sep)
- ; true),
- write_rows(Rows, Opt0),
- close(Out),
- set_output(user_output).
+ write_csv_(Out, Frm, Opt0),
+ close(Out)).
write_csv(File_Name, Frm) :-
write_csv(File_Name, Frm, []).
