Thin compatibility layer for Gray streams
trivial-gray-streams is a trivial library which provides an extremely thin compatibility layer for Gray streams. From David N. Gray's STREAM-DEFINITION-BY-USER proposal: "Common Lisp does not provide a standard way for users to define their own streams for use by the standard I/O functions. This impedes the development of window systems for Common Lisp because, while there are standard Common Lisp I/O functions and there are beginning to be standard window systems, there is no portable way to connect them together to make a portable Common Lisp window system. There are also many applications where users might want to define their own filter streams for doing things like printer device control, report formatting, character code translation, or encryption/decryption."
pkg install cl-trivial-gray-streams