4.2.1 Example – Configuring a tool called directly

In this example, we will add support for perl as a syntax check tool. perl supports the -c option which does syntax checking.

First, we write the init-function:

     (defun flymake-perl-init (buffer)
       (let* ((temp-file (flymake-init-create-temp-buffer-copy
                          buffer 'flymake-create-temp-inplace))
              (local-file  (concat (flymake-build-relative-filename
                                    (file-name-directory
                                     (buffer-file-name
                                      (current-buffer)))
                                    (file-name-directory temp-file))
                                   (file-name-nondirectory temp-file))))
         (list "perl" (list "-wc " local-file))))

flymake-perl-init creates a temporary copy of the buffer contents with the help of flymake-init-create-temp-buffer-copy, and builds an appropriate command line.

Next, we add a new entry to the flymake-allowed-file-name-masks:

     (setq flymake-allowed-file-name-masks
           (cons '(".+\\.pl$"
                   flymake-perl-init
                   flymake-simple-cleanup
                   flymake-get-real-file-name)
                 flymake-allowed-file-name-masks))

Note that we use standard cleanup-function and getfname-function.

Finally, we add an entry to flymake-err-line-patterns:

     (setq flymake-err-line-patterns
           (cons '("\\(.*\\) at \\([^ \n]+\\) line \\([0-9]+\\)[,.\n]"
                   2 3 nil 1)
                 flymake-err-line-patterns))