Add mkly rules

mkly-rules.scm

@@ -0,0 +1,48 @@
+(define shell-path "/usr/bin/bash")
+(define project-name (getcwd-base))
+(define options)
+
+;; Return a list of build rules.
+;;
+;; TARGET is a single target passed on the command line, or "" if none
+;; was supplied. (If multiple targets are passed on the command line,
+;; this function will be called once with each target.)
+;;
+;; Return value is a list of rules, where each rule is a list in
+;; the form (PATTERN COMMAND [ARG ...])
+;;
+;; PATTERN can be
+;; * a symbol - COMMAND will be run when the target passed on the
+;;              command line matches this symbol;
+;; * a string - treated as a regular expression; COMMAND will be run
+;;              when it matches the target passed on the command line
+;; * `else', as the last rule - COMMAND will be run when no other rule matches
+;;
+;; COMMAND and arguments can be any value - lists will be flattened,
+;; all values will be converted to strings, and spaces will be added.
+;; String values will be quoted, which is useful for escaping file
+;; names in the final command to be run.
+(define (rules target)
+  (let* ((subdir (parent target))
+         (branch (vcs-current-branch))
+         (dest   (begin
+                   (when subdir
+                     (chdir subdir)
+                     (set! project-name (getcwd-base)))
+                   (use-dir! (format #f "~:[output-~a~;output/~]"
+                                     branch branch)))))
+    ;; A main.ly could also exist both in the root and in the
+    ;; sub-directories, but this will just compile the root main.ly regardless.
+    `((all main.ly part-*.ly)
+      (dev lilypond
+           -o ,(string-append dest project-name "-pacON")
+           main.ly)
+      (main.ly lilypond -dno-point-and-click
+               -o ,(string-append dest project-name)
+               ,target)
+      ("part-.*\\.ly" lilypond -dno-point-and-click
+                      -o ,(string-append
+                           dest project-name "-"
+                           (file-name-no-extension target))
+                      ,target)
+      (else mkly all))))