# Ruby enhancement suggestion **URL:** \ **Category:** Ruby\ **Created:** [June 2, 2009, 3:05am UTC](https://www.ruby-forum.com/t/ruby-enhancement-suggestion/169299 "2009-06-02T03:05:30Z")\ **Posts on this page:** 5\ **Page:** 1
**Author:** ![steveybaby](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/c57346/32.png) [@steveybaby](https://www.ruby-forum.com/u/steveybaby)\ **Post date:** [June 2, 2009, 3:05am UTC](https://www.ruby-forum.com/t/ruby-enhancement-suggestion/169299/1 "2009-06-02T03:05:30Z")
I’m fairly certain this isn’t the proper place to suggestion minor improvements/extensions to the ruby language, but this is something I constantly find myself wishing was available: # Extension to ruby class Hash class Hash def join(key\_value\_sep="=\>", pair\_sep=",") result = “” self.each { |k,v| result \<\< k.to\_s \<\< key\_value\_sep \<\< v.to\_s \<\< pair\_sep } result.chomp pair\_sep end end I’m sure there’s an even cleaner way to do this (and I’d love to see it!!), but the point is so that I can do something like this: > > hash = {} > > =\> {} > > > (0…20).each {|i| hash[i] = i+1 } > > =\> 0…20 > > > hash.join > > =\> > > “16=\>17,5=\>6,11=\>12,0=\>1,17=\>18,6=\>7,12=\>13,1=\>2,18=\>19,7=\>8,13=\>14,2=\>3,19=\>20,8=\>9,14=\>15,3=\>4,20=\>21,9=\>10,15=\>16,4=\>5,10=\>11” > > > hash.join " maps to ", ", " > > =\> “16 maps to 17, 5 maps to 6, 11 maps to 12, 0 maps to 1, 17 maps to > > 18, 6 maps to 7, 12 maps to 13, 1 maps to 2, 18 maps to 19, 7 maps to 8, > > 13 maps to 14, 2 maps to 3, 19 maps to 20, 8 maps to 9, 14 maps to 15, 3 > > maps to 4, 20 maps to 21, 9 maps to 10, 15 maps to 16, 4 maps to 5, 10 > > maps to 11” Is there currently some easy, builtin way to get this sort of output that I’m simply unaware of?? ---
**Author:** ![steveybaby](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/c57346/32.png) [@steveybaby](https://www.ruby-forum.com/u/steveybaby)\ **Post date:** [June 2, 2009, 3:33am UTC](https://www.ruby-forum.com/t/ruby-enhancement-suggestion/169299/2 "2009-06-02T03:33:33Z")
Steve H. wrote: > class Hash > def join(key\_value\_sep="=\>", pair\_sep=",") > result = “” > self.each { |k,v| result \<\< k.to\_s \<\< key\_value\_sep \<\< v.to\_s \<\< > pair\_sep } > result.chomp pair\_sep > end > end Not too hard in ruby: h = {:a =\> 1, :b =\> 2, :c =\> 3} p h.map{|pair| pair.join("=\>")}.join(",") That’s short enough that I wouldn’t bother with a method, but if you prefer: class Hash def join(key\_value\_sep="=\>", pair\_sep=",") map{|pair| pair.join(key\_value\_sep)}.join(pair\_sep) end end I guess the reason this isn’t standard is that it is not very common (?) to treat the keys and values of a hash as strings, regardless of what they really are (note that the fact that keys are symbols is lost in the code above). ---
**Author:** ![steveybaby](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/c57346/32.png) [@steveybaby](https://www.ruby-forum.com/u/steveybaby)\ **Post date:** [June 2, 2009, 3:35am UTC](https://www.ruby-forum.com/t/ruby-enhancement-suggestion/169299/3 "2009-06-02T03:35:54Z")
> # Extension to ruby class Hash > > it!!), but the point is so that I can do something like this: > =\> “16 maps to 17, 5 maps to 6, 11 maps to 12, 0 maps to 1, 17 maps to > 18, 6 maps to 7, 12 maps to 13, 1 maps to 2, 18 maps to 19, 7 maps to > 8, > 13 maps to 14, 2 maps to 3, 19 maps to 20, 8 maps to 9, 14 maps to 15, > 3 > maps to 4, 20 maps to 21, 9 maps to 10, 15 maps to 16, 4 maps to 5, 10 > maps to 11” > > Is there currently some easy, builtin way to get this sort of output > that I’m simply unaware of?? Pretty print might suit your needs. require ‘pp’ pp hash Regards, Dan ---
**Author:** ![steveybaby](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/c57346/32.png) [@steveybaby](https://www.ruby-forum.com/u/steveybaby)\ **Post date:** [June 2, 2009, 4:01am UTC](https://www.ruby-forum.com/t/ruby-enhancement-suggestion/169299/4 "2009-06-02T04:01:21Z")
Joel VanderWerf wrote: > p h.map{|pair| pair.join("=\>")}.join(",") That is indeed nice and compact. Thanks Joel!! That’ll do quite nicely for my needs. 🙂 Daniel B. wrote: > require ‘pp’ > pp hash Thanks Dan! That’s a cool feature, but not really what I’m looking for in the hash.join idea. It is indeed something I’ll be using in the future though. 🙂 ---
**Author:** ![steveybaby](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/c57346/32.png) [@steveybaby](https://www.ruby-forum.com/u/steveybaby)\ **Post date:** [June 2, 2009, 4:29am UTC](https://www.ruby-forum.com/t/ruby-enhancement-suggestion/169299/5 "2009-06-02T04:29:48Z")
On Jun 1, 2009, at 10:01 PM, Steve H. wrote: > ## Thanks Dan! That’s a cool feature, but not really what I’m looking for in the hash.join idea. It is indeed something I’ll be using in the future though. 🙂 Before the other replies, I was thinking that you just wanted Hash#inspect irb\> hash = {} =\> {} irb\> (0…20).each {|i| hash[i] = i+1 } =\> 0…20 irb\> hash =\> {16=\>17, 5=\>6, 11=\>12, 0=\>1, 17=\>18, 6=\>7, 12=\>13, 1=\>2, 18=\>19, 7=\>8, 13=\>14, 2=\>3, 19=\>20, 8=\>9, 14=\>15, 3=\>4, 20=\>21, 9=\>10, 15=\>16, 4=\>5, 10=\>11} irb\> puts hash.inspect {16=\>17, 5=\>6, 11=\>12, 0=\>1, 17=\>18, 6=\>7, 12=\>13, 1=\>2, 18=\>19, 7=\>8, 13=\>14, 2=\>3, 19=\>20, 8=\>9, 14=\>15, 3=\>4, 20=\>21, 9=\>10, 15=\>16, 4=\>5, 10=\>11} =\> nil irb\> hash.inspect =\> “{16=\>17, 5=\>6, 11=\>12, 0=\>1, 17=\>18, 6=\>7, 12=\>13, 1=\>2, 18=\>19, 7=\>8, 13=\>14, 2=\>3, 19=\>20, 8=\>9, 14=\>15, 3=\>4, 20=\>21, 9=\>10, 15=\>16, 4=\>5, 10=\>11}” It even keeps the type of the key straight for you. irb\> {:sym =\> “I’m a symbol”, ‘string’ =\> “String here!”, 1 =\> ‘Fixnum, too’}.inspect =\> “{1=\>"Fixnum, too", :sym=\>"I’m a symbol", "string"=\>"String here!"}” Of course, you could manage that yourself, too, easily enough with something close to what Joel said: irb\> class Hash irb\> def join(key\_value\_sep=“=\>”, pair\_sep=“,”) irb\> map{|k,v| [k.inspect,v.inspect].join(key\_value\_sep)}.join(pair\_sep) irb\> end irb\> end =\> nil irb\> puts hash.join(" says ", ",\n ") 16 says 17, 5 says 6, 11 says 12, 0 says 1, 17 says 18, 6 says 7, 12 says 13, 1 says 2, 18 says 19, 7 says 8, 13 says 14, 2 says 3, 19 says 20, 8 says 9, 14 says 15, 3 says 4, 20 says 21, 9 says 10, 15 says 16, 4 says 5, 10 says 11 =\> nil Note that #inspect is “smarter” because the individual keys and values can do what is right for them. Try the simple #join varieties with values that are themselves Hashes or Arrays. -Rob Rob B. [http://agileconsultingllc.com](http://agileconsultingllc.com) removed\_email\_address@domain.invalid