Lisp-comparison-operators

LISP-比較演算子

次の表は、数値を比較するLISPがサポートするすべての関係演算子を示しています。 ただし、他の言語の関係演算子とは異なり、LISP比較演算子は3つ以上のオペランドを取ることができ、数字のみで機能します。

変数 A が10を保持し、変数 B が20を保持すると仮定します-

Operator	Description	Example
=	Checks if the values of the operands are all equal or not, if yes then condition becomes true.	(= A B) is not true.
/=	Checks if the values of the operands are all different or not, if values are not equal then condition becomes true.	(/= A B) is true.
>	Checks if the values of the operands are monotonically decreasing.	(> A B) is not true.
<	Checks if the values of the operands are monotonically increasing.	(< A B) is true.
>=	Checks if the value of any left operand is greater than or equal to the value of next right operand, if yes then condition becomes true.	(>= A B) is not true.
⇐	Checks if the value of any left operand is less than or equal to the value of its right operand, if yes then condition becomes true.	(⇐ A B) is true.
max	It compares two or more arguments and returns the maximum value.	(max A B) returns 20
min	It compares two or more arguments and returns the minimum value.	(min A B) returns 10

例

main.lispという名前の新しいソースコードファイルを作成し、次のコードを入力します。

(setq a 10)
(setq b 20)
(format t "~% A = B is ~a" (= a b))
(format t "~% A/= B is ~a" (/= a b))
(format t "~% A > B is ~a" (> a b))
(format t "~% A < B is ~a" (< a b))
(format t "~% A >= B is ~a" (>= a b))
(format t "~% A <= B is ~a" (<= a b))
(format t "~% Max of A and B is ~d" (max a b))
(format t "~% Min of A and B is ~d" (min a b))

実行ボタンをクリックするか、Ctrl + Eを入力すると、LISPはすぐに実行し、返される結果は-

A = B is NIL
A/= B is T
A > B is NIL
A < B is T
A >= B is NIL
A <= B is T
Max of A and B is 20
Min of A and B is 10