I/O Expressions

A set of expressions related to input/output using files, streams, readers and sockets.

Some of these expressions are quite advanced and may be dangerous for beginners.

Accessing files can be quite slow as it relies on the machine's file system.

To avoid the program slowing down it may be preferable to access files on a background process.

File Expressions

[a] new file at %String%

Creates a new file at the given path. Returns that file object.

[the] file at %String%

Retrieves the existing file at the given path. Returns that file object. This may be null if the file does not exist.

%File% is [a] file

Whether the file is a file (not a folder.)

%File% is [a] folder

Whether the file is a folder (not a file.)

set {file} to a new file at "test.txt"
set {file} to the file at "test.txt"
assert {file} is a file

File Properties

Property	Description
reader	The file's input stream.
writer	The file's output stream.
contents	The file's string contents.
name	The file name.
path	The file path.

set {file} to a new file at "test.txt"
assert name of {file} is "test.txt"
set the contents of {file} to "hello there"
assert the contents of {file} is "hello there"

Stream Properties

Property	Description
all	The input stream's entire contents.
line	The input stream's next line.

set {file} to a new file at "test.txt"
set {writer} to writer of {file}
write "general kenobi" to {writer}
close {writer} // make sure to close streams when finished
set {reader} to reader of {file}
set {line} to line of {reader}
assert {line} is "general kenobi"
close {reader} // make sure to close streams when finished