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Refactor to Point Free Functions with Ramda using compose and converge

Eliminate Function Arguments (Point-Free Style) with Ramda's Converge

Count Words in a String with Ramda's countBy and invert

Identify and Deal with NaN in JavaScript

Format console.log with CSS and String Template Tags

Convert a QueryString to an Object using Function Composition in Ramda

Create Streams From Iterables With Most.js

Declaratively Map Data Transformations to Object Properties Using Ramda evolve

Public Class Fields with React Components

Select a Subset of Properties from a Collection of Objects in Ramda

Use ES6 Proxies

Curry and Uncurry Functions with Ramda

Create Streams From Single Values With Most.js

Combine Objects with Object.assign and Lodash merge

Set up a native app project with the NativeScript CLI

Add user interaction to Ember.js apps using actions

Include spell-check in text projects using Natural

Check if words sound alike using Natural

Search more efficiently with tries using Natural

Compare similarity of strings through string distance in Natural

Using machine learning classifiers in a new project

Identify the most important words in a document using tf-idf in Natural

Find a word’s definition using WordNet in Natural

Classify text into categories with machine learning in Natural

Classify JSON text data with machine learning in Natural

Tag parts of speech using Natural

Find sequences of words (n-grams) using Natural

Pluralizing nouns and counting numbers with inflectors in Natural

Find the roots of words using stemming in Natural

Create a list with nested reduce functions in ImmutableJS

Use GraphQL's Object Type for Basic Types

P

Create a GraphQL Schema

Use Relay’s Input Object Mutations

P

Convert GraphQL List Type to a Relay Connection Type

P

Add a Relay Node Interface to a GraphQL Schema

P

Add an Interface to a GraphQL Schema

P

Create an Input Object Type for Complex Mutations

P

Write a GraphQL Mutation

P

Use GraphQLList with GraphQLObject Types

P

Use Arguments in a GraphQL Query

P

Use GraphQLNonNull for Required Fields

P

Write a GraphQL Schema in JavaScript

P

Serve a GraphQL Schema as Middleware in Express

P

Use GraphQL's List Type for Collections

P

Use GraphQL Primitive Types

P

Find the intersection of sets with Semigroups

Retrieve and use data from an api with pure functional constructs

Build a data flow for a real world app

Isomorphisms and round trip data transformations

Maintaining structure whilst asyncing

js tutorial about Refactor to Point Free Functions with Ramda using compose and converge

Refactor to Point Free Functions with Ramda using compose and converge

3:33 js

In this lesson we'll take some existing code and refactor it using some functions from the Ramda library, most notably, compose and converge. When we're done, we'll have taken a function with a couple of local variables and parameter references and converted it into more streamlined "point-free" or "tacit" functions.

js tutorial about Eliminate Function Arguments (Point-Free Style) with Ramda's Converge

Eliminate Function Arguments (Point-Free Style) with Ramda's Converge

3:47 js

When doing comparisons inside of functions, you end of relying heavily on the argument passed into the function. Ramda's converge allows you to do comparisons in a Point-Free style allowing you more flexibility with composing and constructing functions. This lesson walks through refactoring a function to Point-Free style using Ramda's Converge.

js tutorial about Count Words in a String with Ramda's countBy and invert

Count Words in a String with Ramda's countBy and invert

4:10 js

You can really unlock the power of ramda (and functional programming in general) when you combine functions. Counting words in a string may seem like a relatively difficult task, but ramda makes it easy by providing a countBy function. This lesson walks through using the countBy to count words in a string.

js tutorial about Identify and Deal with NaN in JavaScript

Identify and Deal with NaN in JavaScript

2:12 js

Dealing with the special NaN value can be tricky in JavaScript. It behaves like a number and not a number at the same time. This lesson explains how to identify it using the isNaN function or the Number.isNaN method.

js tutorial about Format console.log with CSS and String Template Tags

Format console.log with CSS and String Template Tags

4:36 js

The Chrome console allows you to format messages using CSS properties. This lesson walks you through the syntax of formatting your logs with css then refactoring into a template tag function to make formatting more reusable.

js tutorial about Convert a QueryString to an Object using Function Composition in Ramda

Convert a QueryString to an Object using Function Composition in Ramda

2:13 js

In this lesson we'll use a handful of Ramda's utility functions to take a queryString full of name/value pairs and covert it into a JavaScript object so we can access those properties in a more useful way. Along the way, we'll build up a composition and look at the tail, split, map and fromPairs functions, along with the crucial compose function.

js tutorial about Create Streams From Iterables With Most.js

Create Streams From Iterables With Most.js

3:59 js

One of the more powerful functions for creating streams in MostJS is the from function.

In this lesson, we use from to create streams from various Javascript Iterables, take a look at how to throw generator functions into the mix and, for good measure, take a sneak peek at how we can limit our streams using a function called take.

As a bonus, we see what it looks like to use Function.prototype.bind for a quick and dirty way to partially apply arguments to a function.

js tutorial about Declaratively Map Data Transformations to Object Properties Using Ramda evolve

Declaratively Map Data Transformations to Object Properties Using Ramda evolve

2:44 js

We don't always control the data we need in our applications, and that means we often find ourselves massaging and transforming our data. In this lesson, we'll learn how to transform objects in a declarative way using ramda's evolve function.

js tutorial about Public Class Fields with React Components

Public Class Fields with React Components

4:52 js

Public Class Fields allow you to add instance properties to the class definition with the assignment operator (=). In this lesson, we'll look at their use case for simplifying event callbacks and state initialization with a React component.

js tutorial about Select a Subset of Properties from a Collection of Objects in Ramda

Select a Subset of Properties from a Collection of Objects in Ramda

2:59 js

In this lesson we'll take an array of objects and map it to a new array where each object is a subset of the original. We'll look at multiple ways to accomplish this, refactoring our code into a simple and easy to read function using Ramda's map, pick and project functions.

js tutorial about Use ES6 Proxies

Use ES6 Proxies

1:32 js

A JavaScript Proxy allows you to intercept operations performed on objects, arrays, or functions like property lookup, assignment, invocation, property deletion, and more to add custom behavior. In this lesson we look at how to intercept property lookup with the get "trap" that will allow us to get items starting from the end of the array with ease.

js tutorial about Curry and Uncurry Functions with Ramda

Curry and Uncurry Functions with Ramda

3:39 js

Most of the functions offered by the ramda library are curried by default. Functions you've created or that you've pulled in from another library may not be curried. Ramda's curry and curryN functions allow you to take a non-curried function and use it as a curried functions. In the case where you have a manually curried function and you want to just call it like a normal function, you can use uncurryN to get back a function that accepts all of the arguments at once.

js tutorial about Create Streams From Single Values With Most.js

Create Streams From Single Values With Most.js

2:01 js

Most provides many means for creating streams, the simplest of which is the of function. In this lesson, we demonstrate the use of of to lift a single value into a stream. We also show off the just alias of of, as well as, a common method for currying a function.

js tutorial about Combine Objects with Object.assign and Lodash merge

Combine Objects with Object.assign and Lodash merge

2:28 js

Learn how to use Object.assign to combine multiple objects together. This pattern is helpful when writing libraries that have a set of default options where you want to allow a user to override specific options. You'll also learn how to use a third party library to recursively merge nested objects together.

js tutorial about Set up a native app project with the NativeScript CLI

Set up a native app project with the NativeScript CLI

2:18 js

NativeScript is a framework that let's you build JavaScript to native applications. In this lesson, we will set up a native app using the NativeScript command-line interface. We will then take a brief look at some of the project it generates.

js tutorial about Add user interaction to Ember.js apps using actions

Add user interaction to Ember.js apps using actions

3:12 js

In Ember.js, functions that are executed through user interaction with your application are called actions, which can be defined at the route, controller, or component level. In this tutorial, we look at a simple example of defining actions on the controller and hooking it up to our template in order to update properties on the controller.

js tutorial about Include spell-check in text projects using Natural

Include spell-check in text projects using Natural

3:05 js

In this lesson, we’ll see how to use Natural’s probabilistic spell-checker, which uses the trie data structure.

js tutorial about Check if words sound alike using Natural

Check if words sound alike using Natural

2:14 js

In this lesson, we’ll take a look at Natural’s phonetics feature. We’ll learn how to check whether two words sound alike, looking at both the SoundEx and Metaphone algorithms.

js tutorial about Search more efficiently with tries using Natural

Search more efficiently with tries using Natural

1:40 js

Tries are a data structure that provide an efficient way to search for the existence of a word or phrase in a body of text, or to search by prefix.

js tutorial about Compare similarity of strings through string distance in Natural

Compare similarity of strings through string distance in Natural

3:32 js

We will learn how to compare how similar two strings are to each other, examining three algorithms: Jaro-Winkler, Levenshtein, and Dice’s Coefficient.

You should note that none of these algorithms are inherently better than the others. Instead, it's important to choose the one that best fits your text data.

js tutorial about Using machine learning classifiers in a new project

Using machine learning classifiers in a new project

2:03 js

By this point we've seen that classification can take a long time, and with more data, it would take even longer. Luckily, Natural provides support to save your classifiers. In this lesson, we will learn how to save a classifier and load it into a new project in order to classify new data.

js tutorial about Identify the most important words in a document using tf-idf in Natural

Identify the most important words in a document using tf-idf in Natural

5:15 js

Tf-idf, or term frequency-inverse document frequency, is a statistic that indicates how important a word is to the entire document. This lesson will explain term frequency and inverse document frequency, and show how we can use tf-idf to identify the most relevant words in a body of text.

js tutorial about Find a word’s definition using WordNet in Natural

Find a word’s definition using WordNet in Natural

2:43 js

This lesson introduces WordNet, which is an important resource in natural language processing. With WordNet, we can look up a word’s definition, or find its synonyms.

js tutorial about Classify text into categories with machine learning in Natural

Classify text into categories with machine learning in Natural

3:42 js

In this lesson, we will learn how to train a Naive Bayes classifier or a Logistic Regression classifier - basic machine learning algorithms - in order to classify text into categories.

js tutorial about Classify JSON text data with machine learning in Natural

Classify JSON text data with machine learning in Natural

6:05 js

In this lesson, we will learn how to train a Naive Bayes classifier and a Logistic Regression classifier - basic machine learning algorithms - on JSON text data, and classify it into categories.

While this dataset is still considered a small dataset -- only a couple hundred points of data -- we'll start to get better results.

The general rule is that Logistic Regression will work better than Naive Bayes, but only if there is enough data. Since this is still a pretty small dataset, Naive Bayes works better here. Generally, Logistic Regression takes longer to train as well.

This uses data from Ana Cachopo: http://ana.cachopo.org/datasets-for-single-label-text-categorization

js tutorial about Tag parts of speech using Natural

Tag parts of speech using Natural

2:16 js

An important component of many natural language processing projects is being able to identify the grammar of a piece of text. We’ll learn how to do that with Natural’s parts of speech (POS) tagger.

There are many tags, and it's worth looking them up online (search "POS tag symbols") to become familiar with them all.

The setup of the tagger may seem a little strange, but it allows you to replace the lexicon or the rules with a different lexicon or rule set of your choice.

js tutorial about Find sequences of words (n-grams) using Natural

Find sequences of words (n-grams) using Natural

2:06 js

N-grams are sequences of words, where the 'n' stands for the number of words in the sequence. In this lesson, we will see how to find bigrams (2-grams), trigrams (3-grams), and any other length n-gram in a body of text.

js tutorial about Pluralizing nouns and counting numbers with inflectors in Natural

Pluralizing nouns and counting numbers with inflectors in Natural

1:06 js

Inflectors are the modifiers of a word that indicate grammatical categories. While Natural’s coverage of inflectors is not comprehensive, we will show how Natural can pluralize/singularize nouns and count numbers.

js tutorial about Find the roots of words using stemming in Natural

Find the roots of words using stemming in Natural

1:33 js

We will learn about “stemming,” the process of finding the root of words, often in order to group words by a common base root. We will look at the Porter and Lancaster Stemmers, briefly touch on Natural’s support for Russian and Spanish stemmers, and introduce the function to stem and tokenize at the same time.

js tutorial about Create a list with nested reduce functions in ImmutableJS

Create a list with nested reduce functions in ImmutableJS

1:30 js

ImmutableJS reduce functions can be nested to get data out of complex data structures. In this example, we will create an Immutable List from an Immutable Map that is nested inside of an Immutable List that is itself nested inside of an Immutable Map.

js tutorial about Use GraphQL's Object Type for Basic Types

Use GraphQL's Object Type for Basic Types

2:13 js PRO

We can create the most basic components of our GraphQL Schema using GraphQL's Object Types. These types allow us to group related fields together under a specific type, such as a Video or a User, and then allows us to fetch these types when we query our schema. In this video, we'll learn how to write GraphQL Object Types in GraphQL's Schema language, as well as how to create resolvers for them, and ultimately how to query them.

js tutorial about Create a GraphQL Schema

Create a GraphQL Schema

4:16 js

In this video, we’ll take a look at the GraphQL Language and write out our first GraphQL Schema. We’ll use the graphql package available to us through npm to parse our graphql language file and resolve our initial query.

js tutorial about Use Relay’s Input Object Mutations

Use Relay’s Input Object Mutations

4:59 js PRO

In order to support mutations in Relay, there is a requirement that the GraphQL Server exposes mutation fields in a standardized way. This standard includes a way for mutations to accept and emit an identifier string, allowing Relay to track mutations and responses. In this video, we’ll learn how to use a helper available to us through graphql-relay to create Mutation fields that accept clientMutationId’s.

js tutorial about Convert GraphQL List Type to a Relay Connection Type

Convert GraphQL List Type to a Relay Connection Type

4:12 js PRO

In order to properly traverse through collections, Relay-compliant servers require a mechanism to page through collections available in a GraphQL Schema. In this video, we’ll create a Connection type from an existing GraphQL List Type and learn how to access edge information from each collection.

js tutorial about Add a Relay Node Interface to a GraphQL Schema

Add a Relay Node Interface to a GraphQL Schema

7:00 js PRO

The GraphQL Relay Specification requires that a GraphQL Schema has some kind of mechanism for re-fetching an object. For typical Relay-compliant servers, this is going to be the Node Interface. In this video, we’ll add in the Node interface to a GraphQL Schema by using the helpers available in the graphql-relay npm package.

js tutorial about Add an Interface to a GraphQL Schema

Add an Interface to a GraphQL Schema

5:18 js PRO

As we start building out more complex GraphQL schemas, certain fields start to repeat across different types. This is a perfect use-case for the Interface Type made available to us through GraphQL’s Type System. In this video, we’ll go over how to create an Interface Type and how to add it to an existing type in a GraphQL Schema.

js tutorial about Create an Input Object Type for Complex Mutations

Create an Input Object Type for Complex Mutations

2:29 js PRO

When we have certain mutations that require more complex input parameters, we can leverage the Input Object Type in GraphQL. In this video, we’ll learn how to create an Input Object Type and how to add it to a GraphQL Mutation Type.

js tutorial about Write a GraphQL Mutation

Write a GraphQL Mutation

5:14 js PRO

In order to change the data that we can query for in a GraphQL Schema, we have to define what is called a mutation in GraphQL. Mutations allow us to specify ways to create, update, and delete data. It also provides a way to fetch information after the mutation occurs. In this video, we’ll learn how to create a Mutation Type in GraphQL and specify the information we want returned.

js tutorial about Use GraphQLList with GraphQLObject Types

Use GraphQLList with GraphQLObject Types

1:54 js PRO

When working with collections of things in GraphQL, we'll always reach out for the GraphQLList Type. In this video, we'll learn how to use GraphQLList from the graphql package in combination with a GraphQLObject Type to create a field that returns a collection in our Schema.

js tutorial about Use Arguments in a GraphQL Query

Use Arguments in a GraphQL Query

3:58 js PRO

In GraphQL, every field and nested object is able to take in arguments of varying types in order to do common operations like fetching an object by it's ID, filtering, sorting, and more. In this video, we'll update a field to take in an id argument and then learn how to use that argument in our resolve method to fetch a video by its id.

js tutorial about Use GraphQLNonNull for Required Fields

Use GraphQLNonNull for Required Fields

2:05 js PRO

While certain fields in a GraphQL Schema can be optional, there are some fields or arguments that are necessary in order to either fulfill a query, or to provide a guarantee to people using the Schema that some field exists. In this video, we'll take a look at turning an argument in a NonNull argument by applying the GraphQLNonNull type in order to guarantee that the given argument is supplied in the query.

js tutorial about Write a GraphQL Schema in JavaScript

Write a GraphQL Schema in JavaScript

5:38 js PRO

Writing out a GraphQL Schema in the common GraphQL Language can work for simple GraphQL Schemas, but as our application grows, or when we start using more complex types like interfaces or unions, we find that we can’t use a GraphQL Language file in the same way as before. In this video, we’ll learn how to translate a GraphQL Schema written in GraphQL into a GraphQL Schema written in JavaScript.

js tutorial about Serve a GraphQL Schema as Middleware in Express

Serve a GraphQL Schema as Middleware in Express

4:03 js PRO

If we have a GraphQL Schema expressed in terms of JavaScript, then we have a convenient package available to us that let’s us easily serve up our schema on any endpoint in an Express Server. In this video, we’ll use the express-graphql package to serve up our GraphQL Schema as middleware, and also learn how to enable the GraphiQL tool in order to query our GraphQL Schema.

js tutorial about Use GraphQL's List Type for Collections

Use GraphQL's List Type for Collections

2:25 js PRO

In order to handle collections of items in a GraphQL Schema, GraphQL has a List Type. In this video, we’ll learn the syntax for specifying a List of items in a GraphQL Schema.

js tutorial about Use GraphQL Primitive Types

Use GraphQL Primitive Types

1:57 js PRO

GraphQL’s Type System has support for a number of Primitive Types that we can use in our GraphQL Schema definitions. In this video, we’ll take a look at String, Boolean, Int, Float, and ID and how to incorporate them into a GraphQL Schema Definition.

js tutorial about Find the intersection of sets with Semigroups

Find the intersection of sets with Semigroups

5:57 js

We use semigroups to find the intersection of sets, then expand that to work on as many artists as we'd like. Finally, we use foldable to show a pair of intersection and sum to shed more light on the final result set.

js tutorial about Retrieve and use data from an api with pure functional constructs

Retrieve and use data from an api with pure functional constructs

7:07 js

We flesh out the Spotify api with pure functional constructs to retrieve two sets of related artists.

js tutorial about Build a data flow for a real world app

Build a data flow for a real world app

6:12 js

We form a plan to find the common ground between two artists from the spotify api. Then we sketch out a data flow to ensure we have what we need, when we need it.

js tutorial about Isomorphisms and round trip data transformations

Isomorphisms and round trip data transformations

4:30 js

We formally define isomorphisms, make a few, then use them to accomplish normal programming tasks

js tutorial about Maintaining structure whilst asyncing

Maintaining structure whilst asyncing

2:35 js

We take our Promise.all() analogy further by using traversable on a Map(). Then we use two traversals in the same workflow.

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