public int CompareTo(BinaryUnion other)
{
if (other == null)
{
return(1);
}
ISet <Expression> visitedExpressions = new HashSet <Expression>();
ISet <Expression> expression1 = UnionHelper.Iterate(visitedExpressions, Left.AsSequence().Concat(Right)).ToSortedSet();
visitedExpressions.Clear();
ISet <Expression> expression2 = UnionHelper.Iterate(visitedExpressions, other.Left.AsSequence().Concat(other.Right)).ToSortedSet();
return(expression1.SequenceCompare(expression2));
}
public bool Equals(Union other)
{
if (other == null)
{
return(false);
}
ISet <Expression> visitedExpressions = new HashSet <Expression>();
ISet <Expression> expression1 = UnionHelper.Iterate(visitedExpressions, Expressions).ToSortedSet();
visitedExpressions.Clear();
ISet <Expression> expression2 = UnionHelper.Iterate(visitedExpressions, other.Expressions).ToSortedSet();
return(expression1.SequenceEqual(expression2));
}
public int CompareTo(Union other)
{
if (other == null)
{
return(1);
}
ISet <Expression> visitedExpressions = new HashSet <Expression>();
ISet <Expression> expression1 = UnionHelper.Iterate(visitedExpressions, Expressions).ToSortedSet();
visitedExpressions.Clear();
ISet <Expression> expression2 = UnionHelper.Iterate(visitedExpressions, other.Expressions).ToSortedSet();
return(expression1.SequenceCompare(expression2));
}
public override Expression Optimize()
{
ISet <Expression> visitedExpressions = new HashSet <Expression>();
return(new Union(UnionHelper.Iterate(visitedExpressions, Left.AsSequence().Concat(Right))).Optimize());
}
internal override void ToString(StringBuilder builder)
{
ISet <Expression> visitedExpressions = new HashSet <Expression>();
UnionHelper.ToString(builder, UnionHelper.Iterate(visitedExpressions, Left.AsSequence().Concat(Right)).ToSortedSet().AsReadOnly(), Priority);
}
private static Expression ExtractFromBrackets(Expression expressionA, Expression expressionB)
{
IReadOnlyList <Expression> concatA = expressionA.As <Concat>()?.Expressions;
if (concatA == null)
{
concatA = expressionA.AsSequence().ToList().AsReadOnly();
}
IReadOnlyList <Expression> concatB = expressionB.As <Concat>()?.Expressions;
if (concatB == null)
{
concatB = expressionB.AsSequence().ToList().AsReadOnly();
}
int left = 0;
int right = 0;
int count = Math.Min(concatA.Count, concatB.Count);
while (left < count && concatA[left] == concatB[left])
{
left++;
}
while (right < count - left && concatA[concatA.Count - 1 - right] == concatB[concatB.Count - 1 - right])
{
right++;
}
if (left == 0 && right == 0)
{
return(null);
}
IList <Expression> newConcat = new List <Expression>();
IList <Expression> leftConcat = new List <Expression>();
IList <IList <Expression> > middleUnion = new List <IList <Expression> >();
IList <Expression> rightConcat = new List <Expression>();
for (int i = 0; i < left; i++)
{
leftConcat.Add(concatA[i]);
}
for (int i = 0; i < right; i++)
{
rightConcat.Add(concatB[concatB.Count - 1 - i]);
}
rightConcat = rightConcat.AsReadOnly().FastReverse().ToList();
IList <Expression> middleConcat = new List <Expression>();
for (int i = left; i < concatA.Count - right; i++)
{
middleConcat.Add(concatA[i]);
}
middleUnion.Add(middleConcat);
middleConcat = new List <Expression>();
for (int i = left; i < concatB.Count - right; i++)
{
middleConcat.Add(concatB[i]);
}
middleUnion.Add(middleConcat);
newConcat.AddRange(leftConcat);
newConcat.Add(
UnionHelper.MakeExpression(
middleUnion.Select(
c => ConcatHelper.MakeExpression(c.Where(e => e != Empty.Instance).ToList())
).ToList()
)
);
newConcat.AddRange(rightConcat);
return(ConcatHelper.MakeExpression(newConcat).Optimize());
}
public override Expression Optimize()
{
bool somethingChanged;
ISet <Expression> visitedExpressions = new HashSet <Expression>();
ISet <Expression> set = UnionHelper.Iterate(visitedExpressions, Expressions.Select(e => e.Optimize())).ToHashSet();
do
{
somethingChanged = false;
if (set.Any(e => e.CanBeEmpty()))
{
set = set.Select(e => e.TryToLetItBeEmpty().Optimize()).ToHashSet();
}
if (set.Any(e => e != Empty.Instance && e.CanBeEmpty()))
{
set = set.Where(e => e != Empty.Instance).ToHashSet();
}
IList <Expression> list = set.ToList();
for (int i = 0; i < list.Count; i++)
{
for (int j = 0; j < list.Count; j++)
{
if (i != j && IsASuperSetOfB(list[i], list[j]))
{
list.RemoveAt(j);
j--;
if (i > j)
{
i--;
}
somethingChanged = true;
}
}
}
for (int i = 0; i < list.Count; i++)
{
for (int j = 0; j < list.Count; j++)
{
if (i != j)
{
Expression expression = ExtractFromBrackets(list[i], list[j]);
if (expression != null)
{
list.RemoveAt(j);
if (i > j)
{
i--;
}
list.RemoveAt(i);
list.Add(expression);
j--;
somethingChanged = true;
}
}
}
}
set = list.ToHashSet();
} while (somethingChanged);
return(UnionHelper.MakeExpression(set));
}
internal override void ToString(StringBuilder builder)
{
UnionHelper.ToString(builder, Expressions, Priority);
}