.yalrc

;; Get our hostname.
;;
;;  1. If /etc/hostname exists, then read that.
;;
;;  2. If "hostname" is a binary on the PATH execute it, and return the output
;;
;;  3. Otherwise give up.
;;
(set! hostname (fn* ()
                    (cond
                      (file? "/etc/hostname") (slurp "/etc/hostname")
                      (file:which "hostname") (car (shell (list (file:which "hostname"))))
                      true                    "unknown.host.name")))

;;
;; Trim leading/trailing whichspace from a given string
;;
(set! trim (fn* (str)
                "Trim all leading/trailing whitespace from the given string."
                (let* (res (match "^[ \t\r\n]*([^ \t\r\n]+)[ \t\r\n]*" str))
                  (if (list? res)
                      (car (cdr res))
                      str))))


;; (print) returns the value it prints, which is annoying in the REPL
;; environment, as you'd see repeated output:
;;
;;      > (print 3)
;;      3
;;      3
;;      >
;;
;; To avoid this we create a trivial wrapper function that returns nil
;;
(set! puts (fn* (x)
                (do
                 (print x)
                 nil)))


;;
;; OK now we're done, show a banner and launch the REPL
;;
(print "YAL version %s" (version))
(print "This is ~/.yalrc on %s - %s %s" (trim (hostname)) (os) (arch) )