Book Image

Learn Red ? Fundamentals of Red

By : Ivo Balbaert
Book Image

Learn Red ? Fundamentals of Red

By: Ivo Balbaert

Overview of this book

A key problem of software development today is software bloat, where huge toolchains and development environments are needed in software coding and deployment. Red significantly reduces this bloat by offering a minimalist but complete toolchain. This is the first introductory book about it, and it will get you up and running with Red as quickly as possible. This book shows you how to write effective functions, reduce code redundancies, and improve code reuse. It will be helpful for new programmers who are starting out with Red to explore its wide and ever-growing package ecosystem and also for experienced developers who want to add Red to their skill set. The book presents the fundamentals of programming in Red and in-depth informative examples using a step-by-step approach. You will be taken through concepts and examples such as doing simple metaprogramming, functions, collections, GUI applications, and more. By the end of the book, you will be fully equipped to start your own projects in Red.
Table of Contents (13 chapters)

Getting information from a series

A series can contain values of any type, even a mixture of types. It is often important to know how many items a series contains. This is given by the length? property:

;-- see Chapter05/
data: [A B C D]
length? data ;== 4

If a series has no items, it is empty—the empty? function returns true:

empty-lst: []
length? empty-lst ;== 0
empty? empty-lst ;== true

Selecting an item – pick and /

We can select an item in two ways, using our data: [A B C D] series:

  • By specifying the item index in a so-called path notation, such as data/3 ;== C
  • By specifying the item index with pick, such as pick data 3 ;== C

=> Now answer question 6 from the Questions section...