change language for rule def

1 files changed, 5 insertions, 5 deletions

diff --git a/examples/calc.lisp b/examples/calc.lisp
index 87993e8..7b2f9ef 100644
--- a/examples/calc.lisp
+++ b/examples/calc.lisp
@@ -11,15 +11,15 @@
                (:seq <value> (:eof))
                (:seq <unop> (:eof))
                (:seq <binop> (:eof)))
-          :=> car)
+          :then car)
   (<expr>  :-> (:or <subexpr> <value> <unop> <binop>))
   (<subexpr> :-> (:item)
-             :?? listp
-             :=> (argot:parse calc <subexpr> ))
-  (<value> :-> (:item) :?? numberp)
+             :if listp
+             :then (argot:parse calc <subexpr>))
+  (<value> :-> (:item) :if numberp)
   (<binop> :-> (:seq (:@ lhs <expr>)
                      (:@ rhs (:+ (:seq (:or= + - / * ^ %) <expr>))))
-           :=> (expand-binop lhs rhs))
+           :then (expand-binop lhs rhs))
   (<unop>  :-> (:seq (:or= sin cos tan -) <expr>)))