gc_lock.d

import core.stdc.stdio : printf;
import std.stdio : writefln;
import gc.proxy : _gc;
import core.exception : InvalidMemoryOperationError;

class Resource
{
    int id = id.min;
    
    this(int i) { this.id = i; }
    
    ~this()
    {
        writefln("Entering #%d Resource.dtor().\n", this.id);
        
        if (_gc.gcx.running)
            printf("A GC collection is running!\n");
        
        if (_gc.gcLock.tryLock())
        {
            scope (exit) _gc.gcLock.unlock();
            printf("The GC is ours to command!\n");
        }
        else
            printf("The GC lock is taken!\n");
        
        writefln("Exiting #%d Resource.dtor().\n", this.id);
    }
}

void main()
{
    writefln("Entering main().\n");
    
    auto r1 = new Resource(1);
    destroy(r1);
    
    auto r2 = new Resource(2);
    
    writefln("Exiting main().\n");
}