Emacs: Run Current File

By Xah Lee. Date: . Last updated: .

Here's a emacs command that execute the current file. (the content can be JavaScript code, or python, ruby, bash, golang, etc.)

You need all of the following code.

(defvar xah-run-current-file-before-hook nil "Hook for `xah-run-current-file'. Before the file is run.")

(defvar xah-run-current-file-after-hook nil "Hook for `xah-run-current-file'. After the file is run.")
(defun xah-run-current-go-file ()
  "Run or build current golang file.

To build, call `universal-argument' first.

Version 2018-10-12"
  (when (not (buffer-file-name)) (save-buffer))
  (when (buffer-modified-p) (save-buffer))
  (let* (
         ($outputb "*xah-run output*")
         (resize-mini-windows nil)
         ($fname (buffer-file-name))
         ($fSuffix (file-name-extension $fname))
         ($progName "go")
    (setq $cmdStr (concat $progName " \""   $fname "\" &"))
    (if current-prefix-arg
          (setq $cmdStr (format "%s build \"%s\" " $progName $fname)))
        (setq $cmdStr (format "%s run \"%s\" &" $progName $fname))))
      (message "running %s" $fname)
      (message "%s" $cmdStr)
      (shell-command $cmdStr $outputb )
(defvar xah-run-current-file-map nil "A association list that maps file extension to program path, used by `xah-run-current-file'. First element is file suffix, second is program name or path. You can add items to it.")
   ("php" . "php")
   ("pl" . "perl")
   ("py" . "python")
   ("py2" . "python2")
   ("py3" . "python3")
   ("rb" . "ruby")
   ("go" . "go run")
   ("hs" . "runhaskell")
   ("js" . "deno run")
   ("ts" . "deno run") ; TypeScript
   ("tsx" . "tsc")
   ("mjs" . "node --experimental-modules ")
   ("sh" . "bash")
   ("clj" . "java -cp ~/apps/clojure-1.6.0/clojure-1.6.0.jar clojure.main")
   ("rkt" . "racket")
   ("ml" . "ocaml")
   ("vbs" . "cscript")
   ("tex" . "pdflatex")
   ("latex" . "pdflatex")
   ("java" . "javac")
   ;; ("pov" . "/usr/local/bin/povray +R2 +A0.1 +J1.2 +Am2 +Q9 +H480 +W640")
(defun xah-run-current-file ()
  "Execute the current file.
For example, if the current buffer is x.py, then it'll call 「python x.py」 in a shell.
Output is printed to buffer “*xah-run output*”.
File suffix is used to determine which program to run, set in the variable `xah-run-current-file-map'.

If the file is modified or not saved, save it automatically before run.

URL `http://ergoemacs.org/emacs/elisp_run_current_file.html'
Version 2020-09-24 2021-01-21"
  (let (
        ($outBuffer "*xah-run output*")
        (resize-mini-windows nil)
        ($suffixMap xah-run-current-file-map )
    (when (not (buffer-file-name)) (save-buffer))
    (when (buffer-modified-p) (save-buffer))
    (setq $fname (buffer-file-name))
    (setq $fSuffix (file-name-extension $fname))
    (setq $progName (cdr (assoc $fSuffix $suffixMap)))
    (setq $cmdStr (concat $progName " \""   $fname "\" &"))
    (run-hooks 'xah-run-current-file-before-hook)
     ((string-equal $fSuffix "el")
      (load $fname))
     ((string-equal $fSuffix "go")
     ((string-equal $fSuffix "java")
        (shell-command (format "javac %s" $fname) $outBuffer )
        (shell-command (format "java %s" (file-name-sans-extension
                                          (file-name-nondirectory $fname))) $outBuffer )))
     (t (if $progName
              (message "Running")
              (shell-command $cmdStr $outBuffer ))
          (error "No recognized program file suffix for this file."))))
    (run-hooks 'xah-run-current-file-after-hook)))

You can define a keyboard shortcut such as F8 for it.

[see Emacs: How to Define Keys]

Compile TypeScript

For TypeScript, see Emacs: Compile TypeScript File

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