How to Load Lisp Source Code from an InputStream in ABCL's Interpreter

Is it possible for ABCL's interpreter to load Lisp source code directly from an InputStream?

(load "input-stream")

Yes, ABCL (Armed Bear Common Lisp) allows you to load Lisp source code from an InputStream. This capability is essential for dynamically loading code or when you need to evaluate code provided at runtime without loading from a file system.

(defun load-from-stream (input-stream)
  (let ((code (read input-stream)))
    (eval code)))

Causes

• Incorrect handling of InputStream: Not all input streams can be correctly parsed as Lisp source.
• Stream encoding issues: The encoding of the input stream must match the expected encoding of the Lisp source.

Solutions

• Use the `read` function to read from an InputStream and evaluate using `eval`.
• Ensure the correct encoding of the InputStream with `(setf (stream-external-format stream) :utf-8)` if necessary.

Mistake: Forgetting to properly manage the InputStream's closing once the operation is complete.

Solution: Always close the stream using `(close stream)` to avoid resource leaks.

Mistake: Not checking for EOF (End of File) which can lead to errors during processing.

Solution: Implement checks for EOF to gracefully handle the end of input.