Issue 19842 - only class member functions must be used be used as slots

[dukc]

From the bug report:

import std.signals;
import std.stdio;

class Test
{
    mixin Signal!(int);

    void run ()
    {
        emit (1);
    }
}

class Tester
{
    void initialize ()
    {
        Test test = new Test ();
        test.connect ((int a) => trigger (a));
    }

    void trigger (int a)
    {
        writeln (a);
    }
}

Because (int a) => trigger (a) is not referring to any variable in initialize, it's easy to think it's the same as &this.trigger, but it's not. I'm attempting to be more clear on this.

[dlang-bot]

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Bugzilla references

Auto-close	Bugzilla	Severity	Description
✗	19842	critical	std.signals Segfault when connecting with a lambda

Testing this PR locally

If you don't have a local development environment setup, you can use Digger to test this PR:

dub run digger -- build "master + phobos#8137"

[dukc]

Oops, forgot to target stable. Let's try again.