Add plus and minus symbols to lexer

3 files changed, 13 insertions, 2 deletions

diff --git a/input/add-loop.asm b/input/add-loop.asm
index e24a7e6..6379831 100644
--- a/input/add-loop.asm
+++ b/input/add-loop.asm
@@ -12,8 +12,8 @@
         jrl CHECK
 LOOP:
         add $9 $fp $5
-        load $7 0($9)
-        load $8 1($9)
+        load $7 -0($9)
+        load $8 +1($9)
         add $7 $7 $8
         store $7 0($9)
         addi $5 $5 0x1
diff --git a/src/lex.lisp b/src/lex.lisp
index eea0709..d5c77a1 100644
--- a/src/lex.lisp
+++ b/src/lex.lisp
@@ -54,6 +54,9 @@ Comments start with a semi-colon ';' and all tokens after are ignored."
       ((char= chr #\:) 'colon)
       ((char= chr #\$) 'dollar)
 
+      ((char= chr #\+) 'plus)
+      ((char= chr #\-) 'minus)
+
       ((digit-char-p chr)
        (read-immediate chr))
 
diff --git a/t/lex.lisp b/t/lex.lisp
index ab0ed99..dfa632a 100644
--- a/t/lex.lisp
+++ b/t/lex.lisp
@@ -31,6 +31,14 @@
       (read-this "$"
                  (is (eq (lex:read-token) 'lex::dollar))))
 
+(test read-token-reads-plus
+      (read-this "+"
+                 (is (eq (lex:read-token) 'lex::plus))))
+
+(test read-token-reads-minus
+      (read-this "-"
+                 (is (eq (lex:read-token) 'lex::minus))))
+
 (test read-token-ignores-space
       (read-this " ("
                  (is (eq (lex:read-token) 'lex::left-paren))))