Last active
December 23, 2015 02:49
-
-
Save c-spencer/6569571 to your computer and use it in GitHub Desktop.
Simple demo of type construction from Datomic with core.typed and a little glue
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| ; Create a type extractor for this database. | |
| (dat/create-typer create-type "datomic:mem://jelp") | |
| ; Use to reify a User type | |
| (create-type User "User") | |
| ; Create Admin type from User, with a fixed :user/group | |
| ; Lets Admins be used wherever a User is, and be statically checked. | |
| (create-type Admin "User" {:user/group (Value "admin")}) | |
| (ann my-admin Admin) | |
| (def my-admin {:user/id "my-id" | |
| :user/email "my@email.com" | |
| :user/password "my-pass" | |
| :user/group "admin"}) | |
| (ann my-user User) | |
| (def my-user {:user/id "my-id" | |
| :user/email "my@email.com" | |
| :user/password "my-pass" | |
| :user/group "user"}) | |
| ;; Failing cases | |
| (ann my-not-admin Admin) | |
| (def my-not-admin {:user/id "my-id" | |
| :user/email "my@email.com" | |
| :user/password "my-pass" | |
| :user/group "user"}) ; this isn't the admin group | |
| (ann my-invalid-user User) | |
| (def my-invalid-user {:user/id 10 ; should be string | |
| :user/email "my@email.com" | |
| :user/password "my-pass" | |
| :user/group "admin"}) | |
| ;; Storing the optional/mandatory inside the database like so: | |
| { :db/id #db/id[:db.part/types] | |
| :type/name "User" | |
| :type/mandatory [:user/id | |
| :user/email | |
| :user/password | |
| :user/group] | |
| :type/optional [:user/forename | |
| :user/surname] } |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment