Parser doesn't accept `|` as a valid character unless it's within a string.

[Idorobots]

The rule for Special symbols is missing the bar.

;; Spartan REPL. Type ;help for help.
2 | "test | bar"
;; "test | bar"
3 | test-|bar
;; input(1,0): Not a valid Spartan file:
;;   1 |23
;;     |^^
;;   2 |"test | bar"
;;     |^^^^^^^^^^^^
;;   3 |test-|bar
;;     |^^^^^^^^^
;;   4 |
;;     |