silence a warning about _1, and elided lifetimes

[mvidner]

Problem

   Compiling zypp-agama-sys v0.1.0 (/checkout/rust/zypp-agama/zypp-agama-sys)
warning: zypp-agama-sys@0.1.0: In file included from /usr/include/boost/bind.hpp:30,
warning: zypp-agama-sys@0.1.0:                  from callbacks.cxx:1:
warning: zypp-agama-sys@0.1.0: /usr/include/boost/bind.hpp:36:1: note: '#pragma message: The practice of declaring the Bind placeholders (_1, _2, ...) in the global namespace is deprecated. Please use <boost/bind/bind.hpp> + using namespace boost::placeholders, or define BOOST_BIND_GLOBAL_PLACEHOLDERS to retain the current behavior.'
warning: zypp-agama-sys@0.1.0:    36 | BOOST_PRAGMA_MESSAGE(
warning: zypp-agama-sys@0.1.0:       | ^~~~~~~~~~~~~~~~~~~~

warning: hiding a lifetime that's elided elsewhere is confusing
   --> agama-lib/src/storage/client/zfcp.rs:133:9
    |
133 |         &self,
    |         ^^^^^ the lifetime is elided here
134 |         controller_id: &str,
135 |     ) -> Result<ControllerProxy, ServiceError> {
    |                 ^^^^^^^^^^^^^^^ the same lifetime is hidden here
    |
    = help: the same lifetime is referred to in inconsistent ways, making the signature confusing
    = note: `#[warn(mismatched_lifetime_syntaxes)]` on by default

Solution

Follow the hint in the warning message

Testing

It still compiles

[jreidinger]

are both lifetime needed? I expect just one of them here

[mvidner]

Whichever you mean, I disagree:

impl ZFCPClient<'a>

error[E0261]: use of undeclared lifetime name 'a

impl<'a> ZFCPClient

error[E0726]: implicit elided lifetime not allowed here

impl<'a> ZFCPClient<'_>

This does compile but serves only to obscure the meaning.

[jreidinger]

in fact the third one is correct for me as it said impl use lifetime a, and let auto generate lifetime of struct itself. But as it has same lenght, it does not matter much for me.