if (b->left->type == Xvar)
type_err(c, "info: variable '%v' was set as %1 here.",
cast(var, b->left)->var->where_set, t, rules, NULL);
if (b->left->type == Xvar)
type_err(c, "info: variable '%v' was set as %1 here.",
cast(var, b->left)->var->where_set, t, rules, NULL);