Welcome to the Lounge

honey the codewitch wrote:

collection equality comparison

honey the codewitch wrote:

it implements System.IProgress<T>

honey the codewitch wrote:

You should see my _LRItemSetComparer class. It's awful.

honey the codewitch wrote:

to drive you to drink.

Sander Rossel wrote:

lack of braces and leading underscores

for(int ic=Count,i=0;i<ic;++i)
{
    foreach(var kvp in this[i])
    {
        if (!nts.Contains(kvp.Value.Left))
            nts.Add(kvp.Value.Left);
    }
}

for(int ic=Count,i=0;i<ic;++i)
    foreach(var kvp in this[i])
        if (!nts.Contains(kvp.Value.Left))
            nts.Add(kvp.Value.Left);

Jon McKee wrote:

Now tremble before me

if (whatever)
    DoSomething();
    DoSomethingElse();
    DoAThirdThing();

Sander Rossel wrote:

I want to think about what my code is doing and should be doing

Jon McKee wrote:

on the flip-side you can accidentally add code inside a brace that isn't meant to be looped (albeit probably less common)

Jon McKee wrote:

braces vs no braces is exactly a specification of what the code should or should not be doing on a static basis

if (x)
//   DoSomething(); Commented out for now.
AlwaysDoThis();

if (x)
   if (y)
      DoSomething();
   else
      DoSomethingElse();

Sander Rossel wrote:

Only as you said, should do one thing vs. should do x things, but that's something that changes with specs, and both can be easily changed.
The difference is that when the specs are changed to "if x do y and now also z" the code with braces is almost certain to be changed correctly, but without braces that change is more likely to cause a bug.

//if (x)
//   DoSomething(); Commented out for now.
AlwaysDoThis();

if (x)
{
//   DoSomething(); Commented out for now.
}
AlwaysDoThis();

if (x)
{
   if (y)
      DoSomething();
   else
      DoSomethingElse();
}

							}
						}
					}
				}
			}
		}
        ++i;
	}
}

void ProcessThing(Thing thingy)
{
   try
   {
      ProcessFoos(thingy.Foos);
   }
   catch (Exception ex)
   {
      // Handle error.
   }
}

void ProcessFoos(List<Foo> foos)
{
   foreach (var foo in foos)
   {
      ProcessBars(foo.Bars);
   }
}

void ProcessBars(List<Bar> bars)
{
   foreach (var bar in bars)
   {
      ProcessStuff(bar.Stuff);
   }
}

// ...

static void _FillLRClosureInPlace(CfgDocument cfg,IProgress<CfgLalr1Progress> progress, ICollection<LRItem> result)
{
	var done = false;
	while (!done)
	{
		done = true;
		var l = result.ToArray();
		for (var i = 0; i < l.Length; ++i)
		{
			if(null!=progress)
				progress.Report(new CfgLalr1Progress(CfgLalr1Status.ComputingClosure, i));
			var item = l[i];
			var next = item.RightIndex < item.Rule.Right.Count ? item.Rule.Right[item.RightIndex] : null;
			if (item.RightIndex < item.Rule.Right.Count)
			{
				if (cfg.IsNonTerminal(next))
				{
					for (int jc = cfg.Rules.Count, j = 0; j < jc; ++j)
					{
						var r = cfg.Rules[j];
						if (r.Left == next)
						{
							var lri = new LRItem(r, 0);
							if (!result.Contains(lri))
							{
								done = false;
								result.Add(lri);
							}
						}
					}
				}
			}
		}
	}
}

static void _FillLRClosureInPlace(CfgDocument cfg, IProgress<CfgLalr1Progress> progress, ICollection<LRItem> result)
{
    var done = false;
    while (!done)
    {
        done = true;
        var l = result.ToArray();
        for (var i = 0; i < l.Length; i++)
        {
            progress?.Report(new CfgLalr1Progress(CfgLalr1Status.ComputingClosure, i));
            var item = l[i];
            var next = item.RightIndex < item.Rule.Right.Count ? item.Rule.Right[item.RightIndex] : null;
            if (item.RightIndex < item.Rule.Right.Count && cfg.IsNonTerminal(next))
            {
                done = HandleRules(cfg, next, result);
            }
        }
    }
}

private static bool HandleRules(CfgDocument cfg, object next, ICollection<LRItem> result)
{
    bool done = true;
    // cfg.Rules.Count doesn't change, does it?
    for (int j = 0; j < cfg.Rules.Count; j++)
    {
        var r = cfg.Rules[j];
        done = HandleRule(r, next, result);
    }
    return done;
}

private static bool HandleRule(Rule r, object next, ICollection<LRItem> result)
{
    bool done = true;
    if (r.Left == next)
    {
        var lri = new LRItem(r, 0);
        // I think this communicates intent more clearly.
        done = result.Contains(lri);
        if (!done)
        {
            result.Add(lri);
        }
    }
    return done;
}