import { GraphQLScalarType } from "https://dotland.deno.dev/x/graphql_deno@v15.0.0/lib/type/definition.d.ts";

Scalar Type Definition

The leaf values of any request and input values to arguments are Scalars (or Enums) and are defined with a name and a series of functions used to parse input from ast or variables and to ensure validity.

Example:

const OddType = new GraphQLScalarType({
  name: 'Odd',
  serialize(value) {
    return value % 2 === 1 ? value : null;
  }
});