IO on Lists of Character Codes

This package defines IO predicates that read from, or write to, a list of character codes (a string). There are also predicates to open a stream referring to a list of character codes. The stream may be used with general Stream IO predicates.

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 list of character codes using format/3 (see section Input and Output of Terms). 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 list of character codes using write/2 (see section Input and Output of Terms). 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.

open_chars_stream(+Chars, -Stream)

Stream is opened as an input stream to an existing list of character codes. The stream may be read with the Stream IO predicates and must be closed using close/1. The list is copied to an internal buffer when the stream is opened and therefore be a ground list of character codes at that point.

with_output_to_chars(+Goal, -Chars)

with_output_to_chars(+Goal, ?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.