System.Linq.Expressions.Expression.VerifyOpTrueFalse C# (CSharp) Method

        private static void VerifyOpTrueFalse(ExpressionType nodeType, Type left, MethodInfo opTrue, string paramName)
        {
            ParameterInfo[] pmsOpTrue = opTrue.GetParametersCached();
            if (pmsOpTrue.Length != 1)
                throw Error.IncorrectNumberOfMethodCallArguments(opTrue, paramName);

            if (!ParameterIsAssignable(pmsOpTrue[0], left))
            {
                if (!(left.IsNullableType() && ParameterIsAssignable(pmsOpTrue[0], left.GetNonNullableType())))
                    throw Error.OperandTypesDoNotMatchParameters(nodeType, opTrue.Name);
            }
        }