This package defines I/O predicates that read from, or write to, a code-list. There are also predicates to open a stream referring to a code-list. The stream may be used with general Stream I/O predicates.
Note that the predicates in this section properly handle wide characters, irrespectively of the wide character encodings selected.
Please note: here, the term chars refers to a code-list,
rather than to a char-list.
This library fully supports multiple SICStus run-times in a process.
To load the package, enter the query
| ?- use_module(library(charsio)).
format_to_chars(+Format, :Arguments, -Chars)
format_to_chars(+Format, :Arguments, ?S0, ?S)
Prints Arguments into a code-list using format/3
(see Term I/O). Chars is unified with the list,
alternatively S0 and S are unified with the head
and tail of the list, respectively.
write_to_chars(+Term, -Chars)
write_to_chars(+Term, ?S0, ?S)
A specialized format_to_chars/[3,4]. Writes Term into a
code-list using write/2 (see Term I/O). Chars is
unified with the list. Alternatively, S0 and S
are unified with the head and tail of the list,
respectively.
write_term_to_chars(+Term, -Chars, +Options)
write_term_to_chars(+Term, ?S0, ?S, +Options)
A specialized format_to_chars/[3,4]. Writes Term into a
code-list using write_term/3 and Options (see Term I/O). Chars is unified with the list.
Alternatively, S0 and S are unified with the
head and tail of the list, respectively.
atom_to_chars(+Atom, -Chars)
atom_to_chars(+Atom, ?S0, ?S)
A specialized format_to_chars/[3,4]. Converts Atom to the
list of characters comprising its name. Chars is
unified with the list, alternatively S0 and S
are unified with the head and tail of the list,
respectively.
number_to_chars(+Number, -Chars)
number_to_chars(+Number, ?S0, ?S)
A specialized format_to_chars/[3,4]. Converts Number to
the list of characters comprising its name. Chars is
unified with the list, alternatively S0 and S
are unified with the head and tail of the list,
respectively.
read_from_chars(+Chars, -Term)
Reads Term from Chars using read/2. The Chars
must, as usual, be terminated by a full-stop, i.e. a .,
possibly followed by layout-text.
read_term_from_chars(+Chars, -Term, +Options)
Reads Term from Chars using read_from_term/3 and
Options. The Chars must, as usual, be terminated by a
full-stop, i.e. a ., possibly followed by
layout-text.
open_chars_stream(+Chars, -Stream)
Stream is opened as an input stream to an existing
code-list. The stream may be read with the Stream I/O
predicates and must be closed using close/1. The
list is copied to an internal buffer when the stream is
opened and must therefore be a ground code-list at that
point.
with_output_to_chars(:Goal, -Chars)
with_output_to_chars(:Goal, ?S0, ?S)
with_output_to_chars(:Goal, -Stream, ?S0, ?S)
Goal is called with the current_output stream set to
a new stream. This stream writes to an internal buffer,
which is, after the successful execution of Goal, converted to a
list of character codes. Chars is unified with the
list, alternatively S0 and S are unified with
the head and tail of the list, respectively.
with_output_to_chars/4 also passes the stream in the
Stream argument. It can be used only by Goal for
writing.