public void VisitBlock(BlockSyntax node)
{
var tokens = node.DescendantTokens().ToList();
var dictionary = ParseTokens(tokens, Operands.All);
var dictionary2 = ParseTokens(tokens, Operators.All);
var metrics = new HalsteadMetrics(
numOperands: dictionary.Values.Sum(x => x.Count),
numUniqueOperands: dictionary.Values.SelectMany(x => x).Distinct().Count(),
numOperators: dictionary2.Values.Sum(x => x.Count),
numUniqueOperators: dictionary2.Values.SelectMany(x => x).Distinct().Count());
_metrics = metrics;
}