Add label processing, mnemonic and label lookup maps

1 files changed, 21 insertions, 0 deletions

diff --git a/src/parse.lisp b/src/parse.lisp
new file mode 100644
index 0000000..8bd8c50
--- /dev/null
+++ b/src/parse.lisp
@@ -0,0 +1,21 @@
+(in-package #:parse)
+
+(defun tokens->ast (program)
+  (let ((program (remove nil (mapcar #'extract-label program))))
+    ;; TODO
+    program))
+
+(let ((i 0))
+  (defun extract-label (line)
+    "Given a series of tokens LINE, determines if LINE is
+in the form STRING {colon}. If it is, then it is treated as a
+label, and pushed onto the stack with the line index.
+
+Note that this function is intended to be called using mapcar,
+so that labels can be added to a map and otherwise removed from
+processing."
+    (trivia:match line
+      ((list (and id (type string))
+             (satisfies (lambda (x) (equal x 'lex::colon))))
+       (progn (push (cons (read-from-string id) i) util:label-loc) nil))
+      (_ (progn (incf i) line)))))