Skip to Content
The Ruby Programming Language
book

The Ruby Programming Language

by David Flanagan, Yukihiro Matsumoto
January 2008
Beginner to intermediate
446 pages
14h 45m
English
O'Reilly Media, Inc.
Content preview from The Ruby Programming Language

Program Encoding

At the lowest level, a Ruby program is simply a sequence of characters. Ruby’s lexical rules are defined using characters of the ASCII character set. Comments begin with the # character (ASCII code 35), for example, and allowed whitespace characters are horizontal tab (ASCII 9), newline (10), vertical tab (11), form feed (12), carriage return (13), and space (32). All Ruby keywords are written using ASCII characters, and all operators and other punctuation are drawn from the ASCII character set.

By default, the Ruby interpreter assumes that Ruby source code is encoded in ASCII. This is not required, however; the interpreter can also process files that use other encodings, as long as those encodings can represent the full set of ASCII characters. In order for the Ruby interpreter to be able to interpret the bytes of a source file as characters, it must know what encoding to use. Ruby files can identify their own encodings or you can tell the interpreter how they are encoded. Doing so is explained shortly.

The Ruby interpreter is actually quite flexible about the characters that appear in a Ruby program. Certain ASCII characters have specific meanings, and certain ASCII characters are not allowed in identifiers, but beyond that, a Ruby program may contain any characters allowed by the encoding. We explained earlier that identifiers may contain characters outside of the ASCII character set. The same is true for comments and string and regular expression literals: they ...

Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
and much more.

Read now

Unlock full access

More than 5,000 organizations count on O’Reilly

AirBnbBlueOriginElectronic ArtsHomeDepotNasdaqRakutenTata Consultancy Services

QuotationMarkO’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.
Julian F.
Head of Cybersecurity
QuotationMarkI wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.
Addison B.
Field Engineer
QuotationMarkI’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.
Amir M.
Data Platform Tech Lead
QuotationMarkI'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.
Mark W.
Embedded Software Engineer

You might also like

Polished Ruby Programming

Polished Ruby Programming

Jeremy Evans
Head First Ruby

Head First Ruby

Jay McGavren

Publisher Resources

ISBN: 9780596516178Errata Page