diff --git a/src/lua.grammar b/src/lua.grammar
index d3ca805..0063d6c 100644
--- a/src/lua.grammar
+++ b/src/lua.grammar
@@ -146,8 +146,8 @@ TableConstructor { "{" (field (fieldsep field) fieldsep?)? "}" }
   digit { std.digit }
 
   Number {
-    digit+ ("." digit+)? ($[eE] $[+\-] digit+)? |
-    "0" $[xX] hex+ ("." hex+)? ($[pP] $[+/-] digit+)?
+    digit+ ("." digit+)? ($[eE] $[+\-]? digit+)? |
+    "0" $[xX] hex+ ("." hex+)? ($[pP] $[+\-]? digit+)?
   }
 
   Comment { "--" ![\n\r]* }