Minimal and good enough error handling library for Clojure/ClojureScript (and also Babashka/nbb)
This library is based on "Good Enough" error handling in Clojure.
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Easy to imagine behavior
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Minimum to remember
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All usage and examples are documented in docstring
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(require '[merr.core :as merr])
;; => nil
;; for ClojureScript
;; (require '[merr.core :as merr :include-macros true])
(merr/let err [foo 1
bar (merr/error)
baz (* bar 2)]
{: err err :foo foo :bar bar :baz baz})
;; => {: err (merr/error), :foo 1, :bar nil, :baz nil}(merr/let err [a 10
b (inc a)
c (inc b)]
(if err
(merr/message err)
(str "c = " c)))
;; => "c = 12"
(merr/let err [a 10
b (merr/error {:message "ERROR"})
c (inc b)]
(if err
(merr/message err)
(str "c = " c)))
;; => "ERROR"(merr/->> 10 ( 1) (- 1))
;; => -10
(merr/->> 10 ((fn [_] (merr/error))) (- 1))
;; => (merr/error)You can specify any keywords as :type, but you may want to define and use specific :type of errors in your project.
In that case, merr.helper is useful.
(require '[merr.helper :as merr.h])
;; => nil
(def custom-error (partial merr.h/typed-error ::custom-error-type))
;; => var?
(def custom-error? (partial merr.h/typed-error? ::custom-error-type))
;; => var?
(custom-error? (custom-error {:message "custom error"}))
;; => truetyped-error? will check child error types, so you can define sub errors via clojure.core/derive.
(derive ::sub-custom-error-type ::custom-error-type)
;; => nil
(custom-error? (merr/error {:type ::sub-custom-error-type}))
;; => trueCopyright © 2018-2022 Masashi Iizuka
Distributed under the Eclipse Public License either version 1.0 or (at your option) any later version.
