/// <summary>
/// Combines a list of <see cref="DifferenceSimplifier"/> delegates into a single one.
/// </summary>
/// <param name="simplifiers">The simplifiers.</param>
/// <returns>The new single <see cref="DifferenceSimplifier"/>.</returns>
/// <exception cref="System.ArgumentNullException"><paramref name="simplifiers"/> is <c>null</c>.</exception>
public static DifferenceSimplifier Combine(IEnumerable <DifferenceSimplifier> simplifiers)
{
if (simplifiers == null)
{
throw new ArgumentNullException(nameof(simplifiers));
}
DifferenceSimplifier current = null;
foreach (var item in simplifiers)
{
if (current == null)
{
current = item;
}
else
{
var previous = current;
current = x => current(previous(x));
}
}
if (current == null)
{
current = x => x;
}
return(current);
}
/// <summary>
/// Adds a simplifier to the differences.
/// </summary>
/// <param name="simplifier">The simplifier to add.</param>
/// <returns><c>this</c> instance.</returns>
public Differencer <T> AddSimplifier(DifferenceSimplifier simplifier)
{
if (simplifier == null)
{
throw new ArgumentNullException(nameof(simplifier));
}
if (_simplifier == null)
{
_simplifier = simplifier;
}
else
{
_simplifier = DifferenceSimplifiers.Combine(_simplifier, simplifier);
}
return(this);
}
