From: Corey Jewett <ml@...>
Date: 2007-08-24T07:46:01+09:00
Subject: Re: ruby shell?


On Aug 23, 2007, at 3:01 PM, Tomas Pospisek's Mailing Lists wrote:
> How about being able to do these things with a Ruby DSL? Like:
>
>   for lines in </etc/passwd> { line.split.map ... } > /tmp/ 
> passwd.changed
>   h = Hash.new < `ls #{my_dir}`.special_sort | `tee /tmp/temp_copy`
>
> That would be nice. The shell would need to be interactive and non- 
> interactive...

I haven't looked at any of the projects already out there, just  
piqued my interest enough to generate this:

corey@leviathan ~> irb
 >> class File
 >>   class << self
 >>     alias :[] new
 >>   end
 >>
?>   def lines &block
 >>     arr = self.readlines
 >>     arr.collect! {|line| yield line} if block_given?
 >>     arr
 >>   end
 >> end
=> nil
 >>
?> module Kernel
 >>   define_method :> do |file|
?>     File.open(file, 'w') <<
?>     case
?>     when self.class.respond_to?(:join): self.join('\n')
 >>     else
?>       self.to_s
 >>     end
 >>   end
 >> end
=> #<Proc:0x014c146c@(irb):14>
 >>
?>
?> File["/etc/passwd"].lines {|line| line =~ /^appserver/ ? nil :  
line }.compact > "/tmp/passwd.changed"
=> #<File:/tmp/passwd.changed>
 >> quit
corey@leviathan ~> diff /etc/passwd /tmp/passwd.changed
27d26
< appserver:*:79:79:Application Server:/var/empty:/usr/bin/false