Comma-err 0.1.0-SNAPSHOT API documentation

comma-err.core documentation

Catch errors in the [result err] style, and use a case statement to handle
them. The error is available in the 'err' var. This is equivalent to a
when-err with a case inside of it.

Examples:
(case-err (identity [5 nil])
  "error1" 6)
;=> returns 5

(case-err (identity [nil (Exception. "unhandled error 1")])
   FileNotFoundException (File/readAllBytes "some/other/file.log")
   TimeoutException      :timeout
   :unhandled_error)
;=> returns :unhandled_error

Takes a function call which would throw, and makes it return [result err].
The value of err is the thrown exception.

Example:
(comma-err (identity 6)                                ;=> [6 nil]
(comma-err (throw (Exception. "Something's wrong"))) ;=> [nil #<Exception java.lang.Exception: Something's wrong>]

Catch errors in the [result err] style, and use a condp statement to handle
them. The error is available in the 'err' var. This is equivalent to a
when-err with a condp inside of it.

Examples:
(condp-err = (identity [5 nil])
  "error1" 6)
;=> returns 5

(condp-err instance? (identity [nil (TimeoutException.)])
   FileNotFoundException (File/readAllBytes "some/other/file.log")
   TimeoutException      :timeout
   :unhandled_error)
;=> returns :timeout

Takes a function call which would return [result err] and makes it throw an
exception if err is not nil. The message of the exception is err.

Example:
(must (identity [5 nil]))                     ;=> 5
(must (identity [nil "Something's wrong"])) ;=> throws an exception

Catch errors in the [result err] style, and handle them somehow. The error
is available as the 'err' var. If error is nil, returns the 'result' value.
Otherwise, returns the result of the block.

Example:
(when-err (identity [5 nil])
  (comment "handle an error here"))
;=> returns 5

(when-err (identity [nil "error"])
  (println "something bad happened")
  (println (str "Error: " err))
  "alternative result")
;=> returns "alternative result"