From: Markus Jais <mjais@...>
Date: 2002-02-18T20:47:10+09:00
Subject: hash question

hello
I read in the pickaxe book that I can also use a Regexp as a hash key

lets says I have this code:

hash = Hash.new
hash["bird"] = "vogel"
hash["lynx"] = "luchs"
hash["snake"] = "schlange"

hash.each {|k,v|
  print k, " -> ", v, "\n" if k =~ /^b/
}

the output is of course:
bird -> vogel


but I like to use the regexp /^b/ before the block
something like

hash[/^b].each {|k,v|
  print k, " -> ", v, "\n" if k =~ /^b/
}

but this does not work. I thought that if this would work
it could be faster because the block is only called 
for the keys which macht the regexp.

any ideas how this could be done.
if I have just overlooked the section in the pickaxe book please
let me know where I can find it.

thanks

markus