Modules

Mocking Modules with jest.mock()

Understand how jest.mock() replaces entire modules with automatic or manual mocks, and how to combine that with jest.requireActual for partial mocking.

Modules and the PowerShell Gallery

Learn how PowerShell packages reusable code into modules and how to discover, install, and publish them via the PowerShell Gallery.

Modules in Fortran

Packaging types, data, and procedures into reusable, compile-time-checked Fortran modules.

Modules in Prolog

Learn how Prolog's module system namespaces predicates, controls visibility, and enables code reuse across larger logic programs.

Modules and require

Learn how Lua organizes reusable code into modules with the require function, package.path, and the standard return-a-table pattern.

F# Best Practices

Guidelines for writing idiomatic, maintainable F# code covering function composition, project organization, and error handling.

Functions and Modules

A practical guide to organizing Erlang code into modules and functions, covering declarations, multiple clauses, arity, and exporting a public API.

Functions and Modules in Elixir

Learn how Elixir organizes code into modules and functions, covering named functions, arity, default arguments, private functions, module attributes, and anony…

Perl Modules and CPAN

Learn how Perl organizes reusable code into modules and how CPAN gives you instant access to over 200,000 community-tested packages.

Tasks and Modules

Understand how Ansible tasks invoke modules to perform idempotent actions, and how to choose the right module for the job.

Modules and Packages in Python

Learn how Python organizes code into reusable modules and packages, and how the import system locates and caches them.

Modules in JavaScript (import/export)

How ES modules split code into reusable files using import and export, and how they differ from CommonJS.

Modules in TypeScript

How TypeScript uses ES module syntax (import/export) to organize code across files, with type-only imports and module resolution basics.

Packages and Go Modules

Learn how Go organizes code into packages and manages dependencies with go.mod using the modules system.

Terraform Modules Explained

Modules are Terraform's mechanism for packaging and reusing configuration. This topic explains what a module is, root vs. child modules, and how module calls c…

Comparable and Enumerable Modules

See how Ruby's Comparable and Enumerable modules let a class gain dozens of methods for free by implementing just one core method each: `<=>` or `each`.

Modules and Mixins

Discover how Ruby modules group related methods and constants, and how mixing them into classes with include, extend, and prepend enables flexible code reuse w…

Terraform Cheat Sheet

Terraform HCL syntax, resource blocks, state management, and CLI commands.

ESM vs CommonJS: What Is the Difference?

ESM (ECMAScript Modules, using import/export) is JavaScript’s standardized, statically analyzable module system, while CommonJS (using require/module.exports)…