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Ruby IRB Helper Method To Pretty-print Object Methods

10.27.2006

| 20610 views |

        A simple method to print out the methods for an object at run time in a nicely formatted and colorized way. Really useful when using irb

Place in your .irbrc for easy usage, example here:
http://dotfiles.org/~sd/.irbrc

usage:
pm object
pm object, :more - shows all methods including base Object methods
pm object, :more, /to/ - shows all methods filtered by regexp

Coded by sebastian delmont

    ANSI_BOLD       = "\033[1m"
    ANSI_RESET      = "\033[0m"
    ANSI_LGRAY    = "\033[0;37m"
    ANSI_GRAY     = "\033[1;30m"

    def pm(obj, *options) # Print methods
      methods = obj.methods
      methods -= Object.methods unless options.include? :more
      filter = options.select {|opt| opt.kind_of? Regexp}.first
      methods = methods.select {|name| name =~ filter} if filter

      data = methods.sort.collect do |name|
        method = obj.method(name)
        if method.arity == 0
          args = "()"
        elsif method.arity > 0
          n = method.arity
          args = "(#{(1..n).collect {|i| "arg#{i}"}.join(", ")})"
        elsif method.arity < 0
          n = -method.arity
          args = "(#{(1..n).collect {|i| "arg#{i}"}.join(", ")}, ...)"
        end
        klass = $1 if method.inspect =~ /Method: (.*?)#/
        [name, args, klass]
      end
      max_name = data.collect {|item| item[0].size}.max
      max_args = data.collect {|item| item[1].size}.max
      data.each do |item| 
        print " #{ANSI_BOLD}#{item[0].rjust(max_name)}#{ANSI_RESET}"
        print "#{ANSI_GRAY}#{item[1].ljust(max_args)}#{ANSI_RESET}"
        print "   #{ANSI_LGRAY}#{item[2]}#{ANSI_RESET}\n"
      end
      data.size
    end

Tags:

Comments

Snippets Manager replied on Sun, 2011/11/27 - 6:17am

Hi pals There's a gem called `ori` to include this functionality, plus it lets you quickly browse ri docs: http://github.com/dadooda/ori, screencast at http://www.screencast-o-matic.com/watch/cXVVYuXpH. Examples follow.


### Request Interactive Method List ###

# Regular expression argument denotes list request.
String.ri //
"".ri //

# Show method names matching a regular expression.
"".ri /case/
"".ri /^to_/
[].ri /sort/
{}.ri /each/

# Show ALL methods, including those private of Kernel.
Hash.ri //, :all => true
Hash.ri //, :all

# Show class methods or instance methods only.
Module.ri //, :access => "::"
Module.ri //, :access => "#"

# Show own methods only.
Time.ri //, :own => true
Time.ri //, :own

# Specify visibility: public, protected or private.
Module.ri //, :visibility => :private
Module.ri //, :visibility => [:public, :protected]

# Filter fully formatted name by given regexp.
Module.ri //, :fullre => /\(Object\)::/

# Combine options.
Module.ri //, :fullre => /\(Object\)::/, :access => "::", :visibility => :private

### Request RI on a Class ###

Array.ri
String.ri
[].ri
"".ri
5.ri

### Request RI on a Method ###

String.ri :upcase
"".ri :upcase
[].ri :sort
Hash.ri :[]
Hash.ri "::[]"
Hash.ri "#[]"

Cheers!

Snippets Manager replied on Thu, 2008/04/17 - 10:34am

First of all thanks a lot for this snippet! Ok, here's a better version. Ruby is OO, right? ;)


class Object
  ANSI_BOLD       = "\033[1m"
  ANSI_RESET      = "\033[0m"
  ANSI_LGRAY    = "\033[0;37m"
  ANSI_GRAY     = "\033[1;30m"

  # Print object's methods
  def pm(*options)
    methods = self.methods
    methods -= Object.methods unless options.include? :more
    filter = options.select {|opt| opt.kind_of? Regexp}.first
    methods = methods.select {|name| name =~ filter} if filter

    data = methods.sort.collect do |name|
      method = self.method(name)
      if method.arity == 0
        args = "()"
      elsif method.arity > 0
        n = method.arity
        args = "(#{(1..n).collect {|i| "arg#{i}"}.join(", ")})"
      elsif method.arity < 0
        n = -method.arity
        args = "(#{(1..n).collect {|i| "arg#{i}"}.join(", ")}, ...)"
      end
      klass = $1 if method.inspect =~ /Method: (.*?)#/
      [name, args, klass]
    end
    max_name = data.collect {|item| item[0].size}.max
    max_args = data.collect {|item| item[1].size}.max
    data.each do |item| 
      print " #{ANSI_BOLD}#{item[0].rjust(max_name)}#{ANSI_RESET}"
      print "#{ANSI_GRAY}#{item[1].ljust(max_args)}#{ANSI_RESET}"
      print "   #{ANSI_LGRAY}#{item[2]}#{ANSI_RESET}\n"
    end
    data.size
  end
end

Now you can happily hit 1.pm Cheers!