Define a hash function for PostprocessorName<hash function>

[SY1104]

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Hello! I encountered the following error while trying to compile my app:

/home/sy/miniforge/envs/moose/x86_64-conda-linux-gnu/include/c++/12.3.0/bits/hashtable_policy.h:1268:23: error: static assertion failed: hash function must be invocable with an argument of key type
1268 |         static_assert(__is_invocable<const _Hash&, const _Key&>{},
     |                       ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/home/sy/miniforge/envs/moose/x86_64-conda-linux-gnu/include/c++/12.3.0/bits/hashtable_policy.h:1268:23: note: 'std::__is_invocable<const std::hash<PostprocessorName>&, const PostprocessorName&>()' evaluates to false
/home/sy/miniforge/envs/moose/x86_64-conda-linux-gnu/include/c++/12.3.0/bits/hashtable_policy.h:1270:25: error: no match for call to '(const std::hash<PostprocessorName>) (const PostprocessorName&)'
1270 |         return _M_hash()(__k);
     |                ~~~~~~~~~^~~~~
make: *** [/home/sy/projects/1/cat/moose/framework/build.mk:151: /home/sy/projects/1/cat/moose/modules/solid_mechanics/build/unity_src/timeintegrators_Unity.x86_64-conda-linux-gnu.opt.lo] Error 1

I think it's better not to modify the files in Miniforge, so I started modifying the code in my own files (/home/sy/projects/1/cat/moose/framework/build/header_symlinks/Postprocessor.h)

// Postprocessor.h
#pragma once

#include <string>
#include <functional>

namespace std
{
    template<>
    struct hash<PostprocessorName>
    {
        std::size_t operator()(const PostprocessorName & key) const
        {
            return std::hash<std::string>()(key.name);
        }
    };
}

During my compilation process, I assumed that there was a member variable named 'name' in the PostprocessorName class,which proved not to exit in the class sadly. I searched all the files but couldn't find the definition of the PostprocessorName class. However, when I customized the PostprocessorName class, I would receive an error stating the redefinition of 'class PostprocessorName'.

May I ask if you can provide a definition for PostprocessorName? Or suggest how I modify my Postprocessor.h file to solve this hashing problem?

Thanks a lot!!! Yours,sincerely.

(Optional) code in question / simulation log / errors

No response

Encountering Errors? Please include diagnostic output

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[GiudGiud]

Hello

PostprocessorName is defined in the MooseTypes.h header.
It's essentially a string, with some limitations on conversions.

Can you paste the system diagnostics obtained with script/diagnostics.sh ? Maybe your compiler isnt a supported version