Modify parser to handle unary operators

1 files changed, 11 insertions, 6 deletions

diff --git a/src/modules/parser/parser.scm b/src/modules/parser/parser.scm
index ceac389..fa9202d 100644
--- a/src/modules/parser/parser.scm
+++ b/src/modules/parser/parser.scm
@@ -21,12 +21,17 @@
 
 (define (p-stmt tokens)
   (match tokens
-    (`(return ,expr semi-colon)
-     (make-stmt (p-expr (list expr))))
+    (('return expr ... 'semi-colon)
+     (make-stmt (p-expr expr)))
     (_ (die))))
 
 (define (p-expr tokens)
-  (match tokens
-    (((? number? int))
-     (make-expr int))
-    (_ (die))))
+  (make-expr
+   (match tokens
+     (((? integer? int))
+      (make-const int))
+     (((or 'sub 'complement) expr ...)
+      (make-unary (car tokens) (p-expr expr)))
+     (('left-paren expr ... 'right-paren)
+      (p-expr expr))
+     (_ (die)))))