# Storing methods in arrays or hashes **URL:** \ **Category:** Ruby\ **Created:** [December 25, 2009, 4:27pm UTC](https://www.ruby-forum.com/t/storing-methods-in-arrays-or-hashes/180668 "2009-12-25T16:27:17Z")\ **Posts on this page:** 5\ **Page:** 1
**Author:** ![Philliam\_A](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/p/278dde/32.png) [@Philliam\_A](https://www.ruby-forum.com/u/Philliam_A)\ **Post date:** [December 25, 2009, 4:27pm UTC](https://www.ruby-forum.com/t/storing-methods-in-arrays-or-hashes/180668/1 "2009-12-25T16:27:17Z")
Hey all, I’m pretty new to ruby, and I absolutely love it. I have aquestion. I have programmed in a language called lua before (which had real full- fledged anonymous functions), and with a lua table, which is Lias version of a hash and an arrary combined, you could do something like this: newtable = { 1 = function() print(“hi from 1”) end, 2 = function() print(“hi from 2”) end } even though some of you haven’t even ever heard of lua before, it’s easy to guess what this does: it creates two keys, 1 and 2, in a table, newtable, and assigns two functions as their values. After doing that, you can do this: newtable1 To call the function stored in newtable[1]. All that begs the question: is something similar available in ruby? ---
**Author:** ![Philliam\_A](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/p/278dde/32.png) [@Philliam\_A](https://www.ruby-forum.com/u/Philliam_A)\ **Post date:** [December 25, 2009, 4:39pm UTC](https://www.ruby-forum.com/t/storing-methods-in-arrays-or-hashes/180668/2 "2009-12-25T16:39:02Z")
On 12/24/2009 08:05 AM, Philliam A. wrote: > Hey all, > I’m pretty new to ruby, and I absolutely love it. I have aquestion. I > have programmed in a language called lua before (which had real full- > fledged anonymous functions), and with a lua table, which is Lias > version of a hash and an arrary combined, you could do something like Just out of curiosity: where is the array in your Lua case? In Ruby you would not need an Array for this - or rather, you need either an Array or a Hash. > newtable1 > > To call the function stored in newtable[1]. All that begs the > question: is something similar available in ruby? Yes. (I’m inclined to say “Of course!” :-)) Please see Bill’s explanation. Additional note: since the advent of Ruby 1.9 you can also use another syntax for anonymous functions: f = -\>(args) { code } newtable = { 1 =\> -\> { puts “hi from 1” }, 2 =\> -\> { puts “hi from 2” }, } If you only have numeric indexes in sequence you can also use an Array instead of a Hash: newtable = [ -\> {}, # index 0 -\> { puts “hi from 1” }, -\> { puts “hi from 2” }, ] Kind regards robert ---
**Author:** ![Philliam\_A](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/p/278dde/32.png) [@Philliam\_A](https://www.ruby-forum.com/u/Philliam_A)\ **Post date:** [December 25, 2009, 4:39pm UTC](https://www.ruby-forum.com/t/storing-methods-in-arrays-or-hashes/180668/3 "2009-12-25T16:39:37Z")
On Dec 24, 4:59 am, Robert K. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > or a Hash. > > > doing that, you can do this: > > syntax for anonymous functions: > > instead of a Hash: > > – > remember.guy do |as, often| as.you\_can - without endhttp://blog.rubybestpractices.com/ Holy crap that’s awesome. Thanks for telling me about the new syntax for anonymous function Rob, it just makes me love ruby even more now. Thanks again guys. ---
**Author:** ![Philliam\_A](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/p/278dde/32.png) [@Philliam\_A](https://www.ruby-forum.com/u/Philliam_A)\ **Post date:** [December 25, 2009, 5:04pm UTC](https://www.ruby-forum.com/t/storing-methods-in-arrays-or-hashes/180668/4 "2009-12-25T17:04:52Z")
On Thu, 2009-12-24 at 16:10 +0900, Philliam A. wrote: > This calls a dispatch. Though I also don’t know how ruby will write it, but I think maybe using symbols is a way. Eva. ---
**Author:** ![Philliam\_A](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/p/278dde/32.png) [@Philliam\_A](https://www.ruby-forum.com/u/Philliam_A)\ **Post date:** [December 25, 2009, 5:00pm UTC](https://www.ruby-forum.com/t/storing-methods-in-arrays-or-hashes/180668/5 "2009-12-25T17:00:09Z")
Philliam A. wrote: > newtable = { 1 = function() print(“hi from 1”) end, > 2 = function() print(“hi from 2”) end > } # here’s an example, similar to the above, but # also passing an argument: newhash = { 1 =\> lambda {|x| puts("#{x} from 1")}, 2 =\> lambda {|x| puts("#{x} from 2")} } newhash[1].call(“hi”) newhash[2][“bye”] # alternate call syntax # produces: hi from 1 bye from 2 Hope this helps, Bill