private IDictionary <MultisetField, MultisetField> ToMultiset()
{
Debug.Assert(this.values != null, "values is null");
var dict = new Dictionary <MultisetField, MultisetField>();
foreach (var v in this.values)
{
var field = new MultisetField(new SymbolToken(v.FieldNameSymbol.Text, v.FieldNameSymbol.Sid), v)
{
Count = 1,
};
// assume that for most cases, the field name is unique.
if (dict.TryGetValue(field, out var existing))
{
existing.Count += 1;
}
else
{
dict.Add(field, field);
}
}
return(dict);
}
/// <inheritdoc />
/// <remarks>
/// Struct equivalence is an expensive operation.
/// </remarks>
public override bool IsEquivalentTo(IonValue other)
{
if (!(other is IonStruct otherStruct))
{
return(false);
}
if (NullFlagOn())
{
return(other.IsNull);
}
if (other.IsNull || otherStruct.Count != Count)
{
return(false);
}
if (_values.Count != otherStruct._values.Count)
{
return(false);
}
var multiset = ToMultiset();
foreach (var v2 in otherStruct._values)
{
var field = new MultisetField(v2.FieldNameSymbol.Text, v2);
if (!multiset.TryGetValue(field, out var mapped) || mapped.Count == 0)
{
return(false);
}
mapped.Count--;
}
return(true);
}
