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Right

As explained in Functional Programming in JavaScript

A right-hand Either case that conventionally carries a successful value.

Right is the success branch of an Either value. It holds the result when a computation succeeds, while Left holds the error side. section 5.3

It is used to keep success and failure separate without throwing away the reason something failed. Mapping functions runs on the right side, so safe pipelines can continue only when a value is present. section 5.3

Lookup result

A successful student lookup returns Right(Student), which can then be unwrapped or passed onward through later operations.

How Functional Programming in JavaScript covers it

How deep it goes
Defines Right as the success case and shows right-biased mapping, but stops short of a full class walkthrough.
Examples
Uses student lookup, URL decoding, and parse chaining to show Right in action.
What it assumes
Assumes basic comfort with function return values and introduces Either from the ground up.
What you can do after
Operate safe pipelines that preserve successful values for later mapping or extraction.
How it connects
Connects to Either, Left, map, getOrElse, and fromNullable.
Cover of Functional Programming in JavaScript
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Related concepts

This explainer was generated by Manning's knowledge graph from the text of Functional Programming in JavaScript. The section links point to the parts of the book it draws on.