From 2d446b3a85dd72886a44397bee37ea45381eab03 Mon Sep 17 00:00:00 2001
From: Brett Saiki <bksaiki@gmail.com>
Date: Mon, 26 Aug 2024 13:46:34 -0700
Subject: [PATCH] add fpcore check

---
 src/syntax/syntax.rkt | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/src/syntax/syntax.rkt b/src/syntax/syntax.rkt
index aa347bf95..1ee7e434d 100644
--- a/src/syntax/syntax.rkt
+++ b/src/syntax/syntax.rkt
@@ -342,9 +342,11 @@
     (cond
       [fpcore ; provided -> TODO: check free variables, props
        (match fpcore
-         [`(! ,props ... (,operator ,args ...)) (void)]
+         [`(! ,props ... (,operator ,args ...))
+          (unless (even? (length props))
+            (error 'register-operator-impl! "umatched property for ~a: ~a" name fpcore))]
          [`(,operator ,args ...) (void)]
-         [_ (raise-herbie-syntax-error "Invalid fpcore for ~a: ~a" name fpcore)])
+         [_ (error 'register-operator-impl! "Invalid fpcore for ~a: ~a" name fpcore)])
        fpcore]
       [else ; not provided => need to generate it
        (define repr (context-repr ctx))