# Objective
The `ArgList::push` family of methods consume `self` and return a new
`ArgList` which means they can't be used with `&mut ArgList` references.
```rust
fn foo(args: &mut ArgList) {
args.push_owned(47_i32); // doesn't work :(
}
```
It's typical for `push` methods on other existing types to take `&mut
self`.
## Solution
Renamed the existing push methods to `with_arg`, `with_ref` etc and
added new `push` methods which take `&mut self`.
## Migration Guide
Uses of the `ArgList::push` methods should be replaced with the `with`
counterpart.
<details>
| old | new |
| --- | --- |
| push_arg | with_arg |
| push_ref | with_ref |
| push_mut | with_mut |
| push_owned | with_owned |
| push_boxed | with_boxed |
</details>