Ruby Basics - Revision history

Scott: /* Control flow */

2014-06-18T20:39:11Z

Control flow

2012-02-29T21:43:40Z

Types

← Older revision		Revision as of 21:43, 29 February 2012
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	* Hash		* Hash
	<source lang="ruby">		<source lang="ruby">
	to_s, to_i, to_a # convert to Strings, to Integer, to Array		to_s, to_i, to_a # convert to Strings, to Integer, to Array
	x.class # to see the class		x.class # to see the class, returns Class object
			x.respond_to? 'values' # see if method x.values is defined
	</source>		</source>
	=== A word on booleans ===		=== A word on booleans ===

2011-10-06T17:42:45Z

Program Structure

← Older revision		Revision as of 17:42, 6 October 2011
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	</source>		</source>
	* The <code>require</code> statement reads and executes a file immediately, if it hasn't already.		* The <code>require</code> statement reads and executes a file immediately, if it hasn't already.
			* The <code>load</code> statement reads and executes the file, whether or not it has already done so.
	* Add this to the bottom of a Ruby file to run it directly (usually for debugging):		* Add this to the bottom of a Ruby file to run it directly (usually for debugging):
	<source lang="ruby">		<source lang="ruby">

2011-10-06T17:35:45Z

Operators

2011-10-06T17:35:05Z

A word on booleans

← Older revision		Revision as of 17:35, 6 October 2011
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	</source>		</source>
	=== A word on booleans ===		=== A word on booleans ===
	Some may be used to thinking that a false value may be represented as a zero, a null string, a null character, or various other things. But in Ruby, all of these are true; in fact, everything is true except false and nil.		Some may be used to thinking that a false value may be represented as a zero, a null string, a null character, or various other things. But in Ruby, all of these are true; in fact, everything is true except <code>false</code> and <code>nil</code>.

	== Variables ==		== Variables ==

2011-10-05T21:51:19Z

Variables

@@ Line 57: / Line 57: @@
 x ||= 10    # assigns 10 to x only if x hasn't yet been defined
 </source>
 == Methods ==

2011-10-05T21:08:27Z

Methods

← Older revision		Revision as of 21:08, 5 October 2011
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	str2.spell # error!		str2.spell # error!
	</source>		</source>

			The <code>return</code> at the end of a method can be omitted. A method always returns the last expression evaluated in its body, regardless of where that happens.

	== Control flow ==		== Control flow ==

2011-10-05T21:06:37Z

Variables

2011-10-05T20:59:09Z

Program Structure

2011-10-05T20:58:53Z

Program Structure

← Older revision		Revision as of 20:58, 5 October 2011
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	puts 'Hello World'		puts 'Hello World'
	</source>		</source>
	* The <code>require</code> statement reads and executes a file immediately, if it hasn't already.		* The <code>require</code> statement reads and executes a file immediately, if it hasn't already.
			* Add this to the bottom of a Ruby file to run it directly (usually for debugging):
			<source lang="ruby">
			if $0 == __FILE__
			main
			end
			</source>

	== Types ==		== Types ==