<PackageReference Include="NUnit" Version="4.2.2" />

NUnit.Framework.Constraints.ReusableConstraint

public class ReusableConstraint : IResolveConstraint
ReusableConstraint wraps a constraint expression after resolving it so that it can be reused consistently.
public ReusableConstraint(IResolveConstraint c)

Construct a ReusableConstraint from a constraint expression

public static ReusableConstraint op_Implicit(Constraint c)

Converts a constraint to a ReusableConstraint

public IConstraint Resolve()

Return the top-level constraint for this expression