diff --git a/docs/grammar/abnf-grammar.txt b/docs/grammar/abnf-grammar.txt
index ba7e197f79..c6c4a1fdbb 100644
--- a/docs/grammar/abnf-grammar.txt
+++ b/docs/grammar/abnf-grammar.txt
@@ -185,6 +185,8 @@ atomic-literal = numeric-literal
 symbol = "!" / "&&" / "||"
        / "==" / "!="
        / "<" / "<=" / ">" / ">="
+       / "&" / "|" / "^"
+       / "<<" / ">>"
        / "+" / "-" / "*" / "/" / "**"
        / "="
        / "(" / ")"