Is there equivalent for PHP's print_r in Ruby / Rails?

Question

In PHP you can do:

print_r($var) or vardump($var)

which prints \"human-readible\" information about variable.

Is there equ

Answer 1

Guess I'm a little late to this, but what about logger.info [debug|warning]? Use this from Controllers and Models. It will show up in your log files (development.log when in dev mode); and the above mentioned <%= debug("str: " + str) %> for views.

These aren't exact answers to your questions but you can also use script/console to load your rails app in to an interactive session.

Lastly, you can place debugger in a line of your rails application and the browser will "hang" when your app executes this line and you'll be able to be in a debug session from the exact line your placed your debugger in the source code.

Answer 2

There's the method inspect which helps. Sometimes calling the to_s method on an object will help (to_s returns a string representation of the object). You can also query methods, local_variables, class_variables, instance_variables, constants and global_variables.

p ['Hello',"G'day",'Bonjour','Hola'].inspect
# >> "[\"Hello\", \"G'day\", \"Bonjour\", \"Hola\"]"

p ['Hello',"G'day",'Bonjour','Hola'].to_s
# >> "HelloG'dayBonjourHola"

p Array.new.methods
# >> ["select", "[]=", "inspect", "compact"...]

monkey = 'baboon'
p local_variables
# >> ["monkey"]

class Something
  def initialize
    @x, @y = 'foo', 'bar'
    @@class_variable = 'gorilla'
  end
end

p Something.class_variables
# >> ["@@class_variable"]

s = Something.new
p s.instance_variables
# >> ["@x", "@y"]

p IO.constants
# >> ["TRUNC", "SEEK_END", "LOCK_SH"...]

p global_variables
# >> ["$-d", "$\"", "$$", "$<", "$_", "$-K"...]