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

        public static CatchBlock MakeCatchBlock(Type type, ParameterExpression variable, Expression body, Expression filter)
        {
            ContractUtils.RequiresNotNull(type, nameof(type));
            ContractUtils.Requires(variable == null || TypeUtils.AreEquivalent(variable.Type, type), nameof(variable));
            if (variable == null)
            {
                TypeUtils.ValidateType(type, nameof(type));
                if (type.IsByRef)
                {
                    throw Error.TypeMustNotBeByRef(nameof(type));
                }

                if (type.IsPointer)
                {
                    throw Error.TypeMustNotBePointer(nameof(type));
                }
            }
            else if (variable.IsByRef)
            {
                throw Error.VariableMustNotBeByRef(variable, variable.Type, nameof(variable));
            }
            RequiresCanRead(body, nameof(body));
            if (filter != null)
            {
                RequiresCanRead(filter, nameof(filter));
                if (filter.Type != typeof(bool)) throw Error.ArgumentMustBeBoolean(nameof(filter));
            }

            return new CatchBlock(type, variable, body, filter);
        }
    }