Proposing to patch the eslip module so that if a buffer-local `elisp-eval-target` has been set, `eval-last-sexp` and similar commands will execute lisp in the context of another buffer.
The use case is when developing elisp to operate on non-elisp buffers,
interacting with functionality for other languages such as when using
LSP.
This change would bring buffer-based development in line with ielm's `ielm-change-working-buffer` behavior.
While the `eval-last-sexp` commands are very ergonomic, there is no way to direct them at another buffer without wrapping the last sexp in `with-current-buffer`. Advising deep into `eval-last-sexp` is difficult because we must call `set-buffer` after computing the elisp we want to evaluate.
With this support available, the users can then update the buffer local in shortcut commands for buffer-based development of elisp for other modes.
I intend to develop a patch. The main difficulty I can identify so
far is setting the buffer at the correct points so that the setup for
evaluation continues to occur in the correct context.