module: add :lang fortran

* feat(fortran): account for f90 and fortran modes

* feat(fortran): initial keybindings

* feat(fortran): basic compilation

* feat(fortran): compilation popup

This customizes the name of the compilation buffer produced by the
`compile` function. We're keeping things simple; Emacs already knows how
to run compilation commands in a popup and parse the results, so let's
let it do its thing.

* feat(fortran): doctor checks

* docs(fortran): installation instructions

* feat(fortran): actual usage of fpm

* feat(fortran): configure compilation popups

* feat(fortran): improved raw gfortran usage

Although it's recommended to do everything through `fpm` to make life
easier.

* docs(fortran): backburner `+intel` for now

* feat(fortran): address PR suggestions

modules/lang/fortran/autoload.el

@@ -0,0 +1,54 @@
+;;; lang/fortran/autoload.el -*- lexical-binding: t; -*-
+
+;; --- GFORTRAN --- ;;
+
+;;;###autoload
+(defun +fortran/gfortran-compile ()
+  "Compile the current buffer using gfortran."
+  (interactive)
+  (compile (format "gfortran %s %s"
+                   (+fortran/fortran-std)
+                   buffer-file-name)))
+
+;;;###autoload
+(defun +fortran/gfortran-run ()
+  "Run the current buffer using gfortran."
+  (interactive)
+  (delete-file "./a.out")
+  (+fortran/gfortran-compile)
+  (while (not (file-exists-p "./a.out"))
+    (sleep-for 1))
+  (compile "./a.out"))
+
+(defun +fortran/fortran-std ()
+  "Which version of Fortran should we target?"
+  (cl-case major-mode
+    (fortran-mode "-std=legacy")
+    (t "")))
+
+;; --- FPM --- ;;
+
+;;;###autoload
+(defun +fortran/fpm-build ()
+  "Build the current project using fpm."
+  (interactive)
+  (compile "fpm build"))
+
+;;;###autoload
+(defun +fortran/fpm-run ()
+  "Run the current project using fpm."
+  (interactive)
+  (compile "fpm run"))
+
+;;;###autoload
+(defun +fortran/fpm-test ()
+  "Test the current project using fpm."
+  (interactive)
+  (compile "fpm test"))
+
+;; --- MISC. --- ;;
+;;;###autoload
+(defun +fortran/compilation-buffer-name (mode)
+  "The name of the buffer produced by `compile'."
+  (interactive)
+  "*fortran-compilation*")