Programmatic

epsilon-clj also allows you to integrate programmatically with your codebase. Overall, it exposes several useful functions which you can call in your code.

generate-all

Given a template directory, model paths and output directory, generate all templates found in the template directory.

(require '[epsilon.generator :as gen])

(gen/generate-all "templates" ["model.xml"] "output" false)

The above example will take all the templates inside templates, combined with model.xml, and generate files inside output. The last boolean false indicates we don't want watch mode.

!!! info This function will validate all models before generating. If failed, generation will halt.

validate-all

Similar to generate-all but only validates models. For example:

(require '[epsilon.generator :as gen])

(gen/validate-all "templates" ["model.xml"] false)

It also takes a boolean to indicate if you want watch mode.

generate

Take a single template and run generation with it.

(require '[epsilon.generator :as gen])

(gen/generate "templates/foo.egx" ["model.xml"] "output")

validate

Take a single EVL file and run validation with it.

(require '[epsilon.generator :as gen])

(gen/validate "templates/foo.evl" ["model.xml"])

watch

Watch over a directory for file changes. It takes a list of predicates which will be run against file changes to determine if it should be kept or not. For example:

(require '[epsilon.generator :as gen])

(gen/watch "templates" ["model.xml"] "output" [egl? egx?])

will trigger a regeneration every time either an EGL or EGX file is changed.

!!! important watch, as well as generate-all and validate-all in watch mode will not block the current thread. Instead, when called in watch mode they will return a map that has 2 keys: :future and :handler.

- `:handler` refers to the function that when called when stop the current watcher.
- `:future` refers to the `CompletableFuture` returned by the watch service. Use this to join the watcher thread.

```clojure
(require '[epsilon.generator :as gen])

(let [{:keys [handler future]} (gen/watch "templates" ["model.xml"] "output")]
    ;; Call this function will stop the watcher thread.
    (handler)
    ;; Wait for the watcher thread to finish and then join it.
    (.get future))
```

The above code block will also work for `generate-all` and `validate-all` in watch mode.