After digging further, I think the best place to make changes isnt inthese
functions, but rather in get-completion-preview-list. Does this sound correct?
Thanks,
Nathan s
Responding to:
> Hello,
>
> When Emacs is accepting input via M-x one can forego writing the whole command
> due to the way emacs completes it. While I'm not skilled enough to implement
> emacs style completion, I do think it would be nice to be able to complete
> incomplete commands when there is only one possible completion. I'm putting
> this
> here instead of in a github pull request because, in all truthfulness, github
> forking and pull-requesting confuses me, and someone told me I could also
> submit my contributions throught this mailing list.
>
> I've modified the functions eval-command and call-interactively to have an
> additional optional argument called auto-complete, which when true retries
> completion before throwing an error. I'm not sure if this is the right way
> to get the behavior I want, but it works. If theres a better way to do this
> I'll gladly try to implement it.
>
> Apologies for the length of this email; I figured it was better to include
> every
> function than just the small bits i changed, but if its not let me know and
> I'll
> do it differently in the future.
>
> Cheers,
> Nathan
>
> Heres the code:
>
> (defun call-interactively (command &optional (input "") auto-complete)
> "Parse the command's arguments from input given the command's
> argument specifications then execute it. Returns a string or nil if
> user aborted."
> (declare (type (or string symbol) command)
> (type (or string argument-line) input))
> ;; Catch parse errors
> (catch 'error
> (let* ((arg-line (if (stringp input)
> (make-argument-line :string input
> :start 0)
> input))
> (cmd-data (or (get-command-structure command)
> (and auto-complete
> (let ((comp (input-find-completions command
> (all-commands))))
> (when (and comp (= 1 (length comp)))
> (get-command-structure (car comp)))))
> (throw 'error (format nil "Command '~a' not found."
> command))))
> (arg-specs (command-args cmd-data))
> (args (loop for spec in arg-specs
> collect (let* ((type (if (listp spec)
> (first spec)
> spec))
> (prompt (when (listp spec)
> (second spec)))
> (fn (gethash type *command-type-hash*)))
> (unless fn
> (throw 'error (format nil "Bad argument
> type: ~s" type)))
> ;; If the prompt is NIL then it's
> ;; considered an optional argument and
> ;; we shouldn't prompt for it if the
> ;; arg line is empty.
> (if (and (null prompt)
> (argument-line-end-p arg-line))
> (loop-finish)
> (funcall fn arg-line prompt))))))
> ;; Did the whole string get parsed?
> (unless (or (argument-line-end-p arg-line)
> (position-if 'alphanumericp (argument-line-string arg-line)
> :start (argument-line-start arg-line)))
> (throw 'error (format nil "Trailing garbage: ~{~A~^ ~}" (subseq
> (argument-line-string arg-line)
>
> (argument-line-start arg-line)))))
> ;; Success
> (prog1
> (apply (command-name cmd-data) args)
> (setf *last-command* command)))))
>
> (defun eval-command (cmd &optional interactivep auto-complete)
> "exec cmd and echo the result."
> (labels ((parse-and-run-command (input)
> (let* ((arg-line (make-argument-line :string input
> :start 0))
> (cmd (argument-pop arg-line)))
> (let ((*interactivep* interactivep))
> (call-interactively cmd arg-line auto-complete)))))
> (multiple-value-bind (result error-p)
> ;; this fancy footwork lets us grab the backtrace from where the
> ;; error actually happened.
> (restart-case
> (handler-bind
> ((error (lambda (c)
> (invoke-restart 'eval-command-error
> (format nil "^B^1*Error In Command
> '^b~a^B': ^n~A~a"
> cmd c (if
> *show-command-backtrace*
> (backtrace-string)
> ""))))))
> (parse-and-run-command cmd))
> (eval-command-error (err-text)
> :interactive (lambda () nil)
> (values err-text t)))
> ;; interactive commands update the modeline
> (update-all-mode-lines)
> (cond ((stringp result)
> (if error-p
> (message-no-timeout "~a" result)
> (message "~a" result)))
> ((eq result :abort)
> (unless *suppress-abort-messages*
> (message "Abort.")))))))
>
> (defcommand colon (&optional initial-input) (:rest)
> "Read a command from the user. @var{initial-text} is optional. When
> supplied, the text will appear in the prompt.
>
> String arguments with spaces may be passed to the command by
> delimiting them with double quotes. A backslash can be used to escape
> double quotes or backslashes inside the string. This does not apply to
> commands taking :REST or :SHELL type arguments."
> (let ((cmd (completing-read (current-screen) ": " (all-commands)
> :initial-input (or initial-input ""))))
> (unless cmd
> (throw 'error :abort))
> (when (plusp (length cmd))
> (eval-command cmd t t))))
