Bug in Lox interpreter - Resolver.cs

[SeanCross]

Your stack is reversed compared to the java one, so you are iterating though the wrong way, and getting the wrong index in your resolver.

Should be private void ResolveLocal(Expr _variable, Token name) { //for (int i = m_Scopes.Count - 1; i >= 0; i--) for (int i = 0; i < m_Scopes.Count; i++) { Scope scope = m_Scopes[i]; if (scope.ContainsKey(name.lexeme)) { m_Iterpreter.Resolve(_variable, i); return; } } }

You can test with this example code:

fun fibonacci(n) {
  if (n <= 1) return n;
  return fibonacci(n - 2) + fibonacci(n - 1);
}

for (var i = 0; i < 10; i = i + 1) {
  print "fibonacci " + i + ": " + fibonacci(i);
}

[ByronMayne]

Thanks for pointing that out! I am not going to lie I knew there was a bug as I was seeing some weird results. I was going to try to find the bug and fix it when I got some spare time, However you solved it so I will update the code later tonight.

Cheers, Byron

[SeanCross]

No worries. I was looking at your implementation to try and find the bug in mine, but you had the same issue. After that I realised that any weird behaviour so far has been the difference between java and c# things that look the same but behave differently (string.substring comes to mind). A few moments of fiddling and we are both fixed.

Regards

Sean

From: Byron Mayne [mailto:notifications@github.com] Sent: Thursday, 21 December 2017 2:25 PM To: ByronMayne/LoxSharp LoxSharp@noreply.github.com Cc: Sean Cross Sean.Cross@catalystrisk.co.nz; Author author@noreply.github.com Subject: Re: [ByronMayne/LoxSharp] Bug in Lox interpreter - Resolver.cs (#1)

Thanks for pointing that out! I am not going to lie I knew there was a bug as I was seeing some weird results. I was going to try to find the bug and fix it when I got some spare time, However you solved it so I will update the code later tonight.

Cheers, Byron

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