Question

I defined a custom instance method in the String class that I want to use in my other ruby files. I can do it by require-ing the file (that I defined my custom method in), but I want to use it naturally (without having to require).

For example: I defined this in my ‘custom_string.rb’ file:

class String
  def set_style(style)
    puts "\n#{self}"
    self.size.times do
    print style
    end
  end
end

Then, to use my set_style method in my ‘test.rb’ file, I have to do this:

require 'custom_string'
puts "hello".set_style("*")

I’m not using a Rails project. Is there a way to include my file into ruby by default (from the ruby command line) so it is available to all files in Ruby?

Answer 1

Ruby 1.9 help:

$ ruby --help
Usage: ruby [switches] [--] [programfile] [arguments]
  -0[octal]       specify record separator (\0, if no argument)
  -a              autosplit mode with -n or -p (splits $_ into $F)
  -c              check syntax only
  -Cdirectory     cd to directory, before executing your script
  -d              set debugging flags (set $DEBUG to true)
  -e 'command'    one line of script. Several -e's allowed. Omit [programfile]
  -Eex[:in]       specify the default external and internal character encodings
  -Fpattern       split() pattern for autosplit (-a)
  -i[extension]   edit ARGV files in place (make backup if extension supplied)
  -Idirectory     specify $LOAD_PATH directory (may be used more than once)
  -l              enable line ending processing
  -n              assume 'while gets(); ... end' loop around your script
  -p              assume loop like -n but print line also like sed
  -rlibrary       require the library, before executing your script
  -s              enable some switch parsing for switches after script name
  -S              look for the script using PATH environment variable
  -T[level=1]     turn on tainting checks
  -v              print version number, then turn on verbose mode
  -w              turn warnings on for your script
  -W[level=2]     set warning level; 0=silence, 1=medium, 2=verbose
  -x[directory]   strip off text before #!ruby line and perhaps cd to directory
  --copyright     print the copyright
  --version       print the version

Take a look on:

-rlibrary       require the library, before executing your script