common-lisphandleerror

ignore-error on Common Lisp

I'm trying to handle errors in Common Lisp easily, but I have some problems.

In particular, I have this function.

(defun function1 (m)
 (ignore-errors (and (condition-1) (condition-2))
   (format t "Error message")))

I just want that if some conditions fail into the 

(and (condition-1) (condition-2))

it's shown the error message, otherwise just 

T

How can I do? There is a better way to handle this type of errors? I looking for something very simple.

Someone can do an example showing how to use ignore-error?

Thank you.

Solution

  • You can use HANDLER-CASE

    CL-USER 101 > (handler-case (and (evenp 2)
                                 (oddp 1))
               (error (c)
                 (princ c)
                 (values)))
T

CL-USER 102 > (handler-case (and (evenp 2)
                                 (/ 3 0)
                                 (oddp 1))
               (error (c)
                 (princ c)
                 (values)))
Division-by-zero caused by / of (3 0).