Ramda Guide
Preface
How to Use This Guide
What is Ramda?
Suggested Prerequisite Knowledge
Related Projects
A Tour of Ramda
Including Ramda In A Project
Documentation, Source Code, REPL, & Cookbook
Community Resources
Where We're Going
Weathering Our First Ramda Experience
Converting Temperature Units (add, multiply, divide)
Comparing Two Temperatures (min, minBy, max, maxBy)
Keep Looking Up (Object Properties)
Our Data: The ISS' Location
Reading Shallow Object Properties (prop, propOr, props, pick, pluck)
Testing Shallow Object Properties (has, propEq, propIs, propSatisfies)
Reading Deeply Nested Object Properties (path, pathOr, paths)
Testing Deeply Nested Object Properties (hasPath, pathEq, pathSatisfies)
Unshakeable Logic
Our Data: Earthquakes
Controlling Flow (ifElse, when, unless)
Functions Instead of && and || (and, or)
Higher-Order Conditionals (both, either)
"I don't not not like your faults..." (not)
Flipping a Functions' "Truthyness" or "Falsyness" (complement)
Logic in Batches (all, allPass, anyPass)
The Functional Version of a switch (cond)
Core Ramda Ideas
"Same Input → Same Output"
Functions' Argument Order
Provide Arguments When You Feel Like It (curry)
Composing Functional Pipelines of Data (o, compose, composeWith, tap)
Grokking the Ramda Documentation's Type Signatures
Updating Objects: Speaking the Lingua Ramda
Our Data: Languages Object
Setting Key/Value Pairs On An Object (assoc, assocPath)
Omitting Keys From an Object (omit, dissoc, dissocPath)
Merging Objects (mergeRight, mergeDeepRight, mergeLeft, mergeWith)
Updating Values If They Exist (evolve)
Strings: Tying Up Loose Ends
Our Data: Footwear
Uppercasing & Lowercasing Text (toUpper, toLower)
Scanning Text for Matches (match)
Sanitizing Hashtag Text (replace, trim, test, split)
All About ['L','i','s','t','s']
Our data: Nobel Prizes
What is a List?
Taking & Dropping Items (take, takeLast, takeWhile, drop, dropLast, dropWhile)
First & Last Item Groupings (head, tail, init, last)
Searching for Items (filter, reject, find, indexOf, findIndex)
Calling a Function On Every Item (map, forEach)
Inserting, Removing, & Updating Items (insert, insertAll, remove, without, update)
Reversing, Reordering, & Sorting Items (reverse, move, sort, sortBy)
Splitting Lists (slice, splitAt, splitEvery, splitWhen)
Reducing a List to a Single Value (reduce, reduceWhile, mapAccum)
Getting Unique Items (uniq, uniqBy, uniqWith)
Testing Lists With Conditions (includes, any, all, none, startsWith, endsWith)
Combining Lists (concat, union, union, intersection, difference, symmetricDifference, symmetricDifferenceWith)
Through the Lens
Our Data: Observatories
What is a Lens? (lens, lensIndex, lensProp, lensPath)
Safe Getters for Our Data (view)
Safe Setters for Our Data (set, over)
Misc
Converting an Existing API Into a Functional One (invoker)
Understanding Ramda Further by Recreating Parts of It
Using Ramda With TypeScript
Opinionated Best Practices
The Rule of 3
Type, Param, or Pseudo-Type Declarations
Writing Declarative Code That Tells a Story
You Might Not Need Ramda
Your Next Steps
Introducing FP at Work
How to Guide Others
The Larger FP World

Where We're Going

Meme of Doc Brown from Back to the Future in a Delorean with the text, Classes? Where we're going, we don't need classes

Buckle up! We are about to begin our tour of Ramda.

We will start small and practical, getting a feel for importing and using ramda.

After some practice, we'll take a break and cover Ramda's core ideas. In this section, we'll answer the burning "D-I-Why???" questions you will surely have.

Continuing on the path to enlightenment, we'll dive deep into various Ramda functions and concepts, melt our minds a little bit, and come out the other end empowered by knowledge and confident via practice.

By the end of this guide, you will be able to:

understand a majority of Ramda's most valuable functions
use functional programming to start solving problems functionally at work
guide others
continue on your functional programming path to enlightenment, wherever it may lead

Ramda Guide

Where We're Going