This repository contains unofficial patterns, sample code, or tools to help developers build more effectively with Fauna. All Fauna Labs repositories are provided “as-is” and without support. By using this repository or its contents, you agree that this repository may never be officially supported and moved to the Fauna organization.

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FQL utilities

This repo contains code for user-defined functions (UDFs) to accomplish common tasks in Fauna. These UDFs are designed to be deployed with Fauna Schema Migrate.

How to use

• npm init -y
• npm install faunadb
• npm install --save-dev @fauna-labs/faunadb-schema-migrate
• npm install --save-dev @fauna-labs/fql-utilities
• npx fauna-schema-migrate init
• Create a file named tail.js in the fauna/resources directory with the following code:

  import { Tail } from '@fauna-labs/fql-utilities';
  
  export default Tail();
  

• npx fauna-schema-migrate generate
• npx fauna-schema-migrate apply

This creates a UDF named Tail() in your database. Tail() accepts one parameter, an Array, and returns a new array consisting of every element except the first. If the array is empty, Tail() returns an empty array.

You can then call the Tail UDF with the following code:

Let(
  {
    array: [0, 1, 2],
    shortArray: Call("Tail", Var("array"))
  },
  Equals(Count(Var("shortArray")), 2) // true
)

Included packages

Collections

• Tail()
• Zip()

Vector math

• CrossProduct()
• DotProduct()