visitIsExpression method
Implementation
@override
void visitIsExpression(IsExpression e, void arg) {
visit(e.left, arg);
keyword(TokenType.$is);
// Avoid writing `DISTINCT FROM`, but be aware that it effectively negates
// the generated `IS` again.
final negated = e.negated ^ e.distinctFromSyntax;
if (negated) {
keyword(TokenType.not);
}
visit(e.right, arg);
}