diff --git a/srcgen/dotUtils.js b/srcgen/dotUtils.js
index 2fa621e..c05e9e8 100644
--- a/srcgen/dotUtils.js
+++ b/srcgen/dotUtils.js
@@ -65,7 +65,9 @@ function normalizeArgName(name) {
 }
 
 function normalizePropName(propName) {
-  const out = changeCase.snakeCase(propName);
+  let out = changeCase.snakeCase(propName);
+  if (/^\d/.test(out)) // No leading digits.
+    out = 'x' + out;
   if ('type' === out)
     return 'r#' + out;
   return out;