Introduction

The binder package provides functionality to create a (customizable) binding function which takes a template literal and a value for the variable part of the string, normalizes it, and returns the binded string.

Installation

This package should be installed via npm. You must have npm installed first. The following can be run on the commandline to install the binder package with npm:

npm install @nicolawealth/binder

Usage

The binder package is designed to dynamically replace placeholders in strings from provided binding objects which is useful in generating content which adapts to different contexts or inputs.

Some common use cases include:

• Templating systems
• Configuration files
• Email generation
• Customizable notifications
• Report generation
• etc.

Interface

The package exports function binderFactory(bindNormalizer) of exported type binderType where bindNormalizer is an optional string normalizing function which takes in a string and returns a string (i.e. toUpperCase()). binderFactory(bindNormalizer) returns a function which consumes ({value, binds}) where value is a template literal (i.e. a string which contains at least one expression of the form ${...} where ... is replaced by some placeholder string value). Here binds is a key-value paired object which contains keys corresponding to the placeholder parts of value and values which will replace the placeholder parts after binding takes place. If binds is not provided or the appropriate key is not provided within binds, the message returned will indicate so by returning ?{...} in the binded string where ... remains the original placeholder in the template literal. If a normalizing function is specified as bindNormalizer, the string function will be applied to the placeholder value before it's compared to the provided keys.

Sample Function Calls

Providing a Normalizing Function

binderFactory(b=>b.toLowerCase())({value:"My name is ${USERNAME}.", binds:{username:"Bob"}}) returns "My name is Bob."

Multiple Placeholders

binderFactory()({value:"This is a ${func} function with ${number} templated values.", binds:{func: "binder", number: "two"}}) returns "This is a binder function with two templated values."

Failing to Provide a KVP

binderFactory()({value:"My name is ${username}.", binds:{age: "50"}}) returns "My name is ?{username}."

Testing

Tests can be found in binder.test.ts located in binder/src and should be run with sinon, mocha and nyc.