Comments on: What are Ruby Symbols? http://charlesmaxwood.com/what-are-ruby-symbols/ Building Careers by Building Skills Thu, 17 Jun 2010 07:42:40 +0000 hourly 1 http://wordpress.org/?v=3.0 By: Allan http://charlesmaxwood.com/what-are-ruby-symbols/comment-page-1/#comment-1237 Allan Thu, 30 Jul 2009 16:11:21 +0000 http://charlesmaxwood.com/?p=332#comment-1237 Thanks a lot! Thanks a lot!

]]> By: Chuck http://charlesmaxwood.com/what-are-ruby-symbols/comment-page-1/#comment-1235 Chuck Wed, 29 Jul 2009 04:20:38 +0000 http://charlesmaxwood.com/?p=332#comment-1235 The best way I can think of explaining immediate values is numerical values. For example 1 in Ruby is of class Fixnum. If you have a = 1 and b = a, then a and b both refer to the immediate value of 1. If you change it so that a = 2, b still equals 1 because it refers to the immediate value 1. If you have a and b both strings a = "person" and b = a. They both reference the same object. a.reverse! changes a's stored value to "nosrep". If you access b, it also contains "nosrep". With objects of immediate value, you can only change the reference. You cannot change their value. With symbols, they are like Fixnum's. You can refer to them in their immediate and immutable value, but you can't change the Symbol. It's like using 1. You can change your variables so they refer to 2, but then you've changed the reference, not the value itself. Incidentally, you can call to_i on a Symbol to convert it to it's integer equivalent, but the integer doesn't really actually tell you anything useful about the symbol. The best way I can think of explaining immediate values is numerical values. For example 1 in Ruby is of class Fixnum. If you have a = 1 and b = a, then a and b both refer to the immediate value of 1. If you change it so that a = 2, b still equals 1 because it refers to the immediate value 1. If you have a and b both strings a = “person” and b = a. They both reference the same object. a.reverse! changes a’s stored value to “nosrep”. If you access b, it also contains “nosrep”. With objects of immediate value, you can only change the reference. You cannot change their value.

With symbols, they are like Fixnum’s. You can refer to them in their immediate and immutable value, but you can’t change the Symbol. It’s like using 1. You can change your variables so they refer to 2, but then you’ve changed the reference, not the value itself. Incidentally, you can call to_i on a Symbol to convert it to it’s integer equivalent, but the integer doesn’t really actually tell you anything useful about the symbol.

]]> By: Allan http://charlesmaxwood.com/what-are-ruby-symbols/comment-page-1/#comment-1234 Allan Wed, 29 Jul 2009 03:35:46 +0000 http://charlesmaxwood.com/?p=332#comment-1234 "In this example, you still get the Person object back identifying Nikki, but in this case we don’t have the overhead of an object in the key" Isn't (almost) everything in Ruby an Object? You'll still have an object in the key (an instance of Symbol). I don't understand the meaning of "immediate value". Like primitives in Java? “In this example, you still get the Person object back identifying Nikki, but in this case we don’t have the overhead of an object in the key”
Isn’t (almost) everything in Ruby an Object? You’ll still have an object in the key (an instance of Symbol).
I don’t understand the meaning of “immediate value”. Like primitives in Java?

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