% This demonstrates a constraint that composes another constraint
% and uses the addConditionsFrom method to utilize the conditions
% from the composed ConstraintDiagnostic.
classdef IsDouble < matlab.unittest.constraints.Constraint
    
    properties(Constant, GetAccess=private)
        DoubConst = matlab.unittest.constraints.IsInstanceOf(?double);
    end
    
    methods
        function tf = satisfiedBy(constraint, actual)
            tf = constraint.DoubConst.satisfiedBy(actual);
        end
        function diag = getDiagnosticFor(constraint, actual)
            diag = ConstraintDiagnostic;
            
            % Now add conditions from the IsInstanceOf
            % Diagnostic
            otherDiag = constraint.DoubConst.getDiagnosticFor(actual);
            diag.addConditionsFrom(otherDiag)
            
            % ...
        end
    end
end