lisp如何将不同的数字字符串解析为数字

我有一些lisp数字字符串要解析为数字：

“3.000000000 E+00”
“0.0d0”
“3”

在google之后，请参阅：

在google之后，请参阅：

以下是测试：

(string-to-number "3.000000000E+00") ; ==> 3.0
(string-to-number "0.0d0")           ; ==> 0.0d0
(string-to-number "3")               ; ==> 3

(handler-bind ((argument-not-numeric-string #'(lambda (c) (invoke-restart 'restart-with-string "0"))))
  (string-to-number "hello")) ; ==> 0

(handler-bind ((argument-not-numeric-string #'(lambda (c) (use-value 0))))
  (string-to-number "hello")) ; ==> 0

(string-to-number "aa" 16) ; ==> 170

(string-to-number "gf" 16) 
*** - Condition of type ARGUMENT-NOT-NUMERIC-STRING.
The following restarts are available:
USE-VALUE      :R1      USE-VALUE
RESTART-WITH-STRING :R2 RESTART-WITH-STRING
ABORT          :R3      Abort main loop
Break 1 [50]> :r2
Enter new value: "ff"
; ==> 255

以下是测试：

(string-to-number "3.000000000E+00") ; ==> 3.0
(string-to-number "0.0d0")           ; ==> 0.0d0
(string-to-number "3")               ; ==> 3

(handler-bind ((argument-not-numeric-string #'(lambda (c) (invoke-restart 'restart-with-string "0"))))
  (string-to-number "hello")) ; ==> 0

(handler-bind ((argument-not-numeric-string #'(lambda (c) (use-value 0))))
  (string-to-number "hello")) ; ==> 0

(string-to-number "aa" 16) ; ==> 170

(string-to-number "gf" 16) 
*** - Condition of type ARGUMENT-NOT-NUMERIC-STRING.
The following restarts are available:
USE-VALUE      :R1      USE-VALUE
RESTART-WITH-STRING :R2 RESTART-WITH-STRING
ABORT          :R3      Abort main loop
Break 1 [50]> :r2
Enter new value: "ff"
; ==> 255

---

请使用Quicklisp提供的库。

请使用库，可从Quicklisp获得。

请不要发布使用

read

的示例，这些示例至少没有绑定

*read eval*

到

nil

。谢谢Rainer Joswig。请不要发布使用

read

的示例，这些示例至少没有绑定

*read eval*

到

nil

。谢谢Rainer乔斯威格。

(string-to-number "3.000000000E+00") ; ==> 3.0
(string-to-number "0.0d0")           ; ==> 0.0d0
(string-to-number "3")               ; ==> 3

(handler-bind ((argument-not-numeric-string #'(lambda (c) (invoke-restart 'restart-with-string "0"))))
  (string-to-number "hello")) ; ==> 0

(handler-bind ((argument-not-numeric-string #'(lambda (c) (use-value 0))))
  (string-to-number "hello")) ; ==> 0

(string-to-number "aa" 16) ; ==> 170

(string-to-number "gf" 16) 
*** - Condition of type ARGUMENT-NOT-NUMERIC-STRING.
The following restarts are available:
USE-VALUE      :R1      USE-VALUE
RESTART-WITH-STRING :R2 RESTART-WITH-STRING
ABORT          :R3      Abort main loop
Break 1 [50]> :r2
Enter new value: "ff"
; ==> 255