penpot/docs/04-Common-Developer-Guide.md

Common's guide

This section intends to have articles that related to both frontend and backend, such as: code style hints, architecture dicisions, etc...

Assertions

UXBOX source code has this types of assertions:

assert: just using the clojure builtin assert macro.

Example:

(assert (number? 3) "optional message")

This asserts are only executed on development mode. On production environment all assets like this will be ignored by runtime.

spec/assert: using the uxbox.common.spec/assert macro.

Also, if you are using clojure.spec, you have the spec based clojure.spec.alpha/assert macro. In the same way as the clojure.core/assert, on production environment this asserts will be removed by the compiler/runtime.

Example:

(require '[clojure.spec.alpha :as s]
         '[uxbox.common.spec :as us])

(s/def ::number number?)

(us/assert ::number 3)
```

In the same way as the `assert` macro, this performs the spec
assertion only on development build. On production this code will
completely removed.

**spec/verify**: An assertion type that is executed always.

Example:

```clojure
(require '[uxbox.common.spec :as us])

(us/verify ::number 3)
```

This macro enables you have assetions on production code.

**Why don't use the `clojure.spec.alpha/assert` instead of the `uxbox.common.spec/assert`?**

The uxbox variant does not peforms additional runtime checks for know
if asserts are disabled in "runtime". As a result it generates much
simplier code at development and production builds.