9.8.3� �� � lambda � � � ֵ � � ޳ ݲ � � ϶ � � � �� � � � ͼ � � ʾ � � һ � Ա � lambda � � � ְ � � ޳ ݲ � � ϶ � � � ϰ � װ � � � � � � � ľ � Ϊ � � � � ʽ � � ֪ � � � �ʱ � � � � ͨ � � � � � � � ֱ � lambda � � � ִ � � � � � Ϊ� Ƕ ȱ � lambda � � � ִ � � �� � � �� � � �� �� � Ϊ � � � Ƕ ȱ � lambda � � � �� � � �� � � �� �� � Ϊ � � � Ƕ ȱ � lambda � � � �����Ҫ�������¼������
(1)� � � ľ � 䶯 � � � � � y ļ � � � � lambda � � � ֵ � � � � ľ � � � � � ׼ � � � ִ � � � � � � ľ � � � � � IJ � ֵ� � Ϊ � � � ľ � 䶯 � �� � � � Ym � � ʾ � � � Y � Ϊ � � � ľ � 䶯 � � � � � � � � � � ʽ � � � 㣺

(2)� ܱ � lambda � � � �� � � � � � Ͻ Ǧ � 'Ĺ � ϵ
� � � � � � � ֵ ı � � � � � � � ֱ � � � the X1 � � X2 � � � � lambda � � � ִ � � � � ޳ ݲ � � ϶ � � � � ʱ � � Ӧ � � ֤ һ � � � � � ֵ Ľ � Բ � ݺ � S1 � � � � � � � � һ � � � � � ֵ Ľ � Բ � ݲ ۿ � e2 � � � � � �� � � � � Բ � ϵ awesome ݾ � Ϊ � �
� � � � � � � � � � � � � � � � � � � � � � 9-8-6
� � � � � � Բ � � � ݺ � ʽ � � 0-4-9 � � � � � � � Ե � � � � � � creates � ʽ � ޲ � ϶ � � � Ϸ � � ̣ �
� � � � � � � � � � � � � � 9-8-7
� � � � ӳ � � һ � Ա � lambda � � � ִ � � � � � � ޳ ݲ � � ϶ � � � ϰ � װ ʱ � � � � � � � Ͻ Ǧ � 'a' � � � ܱ � lambda � � � �� Ĺ � ϵ � �
� ޲ � ϶ � � � Ϸ � � � � � � � Щ � � ; � أ �