pub fn match_node_ref_imm(op: &TreeNode) -> bool {
    match op.v {
        TreeNode_::Value(ref pv) => match_value_ref_imm(pv),
        _ => false
    }
}
// The only valid ref immediate is a null ref
The only valid ref immediate is a null ref
The only valid ref immediate is a null ref
pub fn match_node_ref_imm(op: &TreeNode) -> bool {
    match op.v {
        TreeNode_::Value(ref pv) => match_value_ref_imm(pv),
        _ => false
    }
}
pub fn match_node_ref_imm ( op : & TreeNode ) -> bool { match op . v { TreeNode_ :: Value ( ref pv ) => match_value_ref_imm ( pv ) , _ => false } }
The only valid ref immediate is a null ref
The only valid ref immediate is a null ref
op
&TreeNode
op
&TreeNode