Last Modified
2016-11-15 11:40:26 -0600
  • prettyprint


Pretty-printer for Ruby objects.

Which seems better?

non-pretty-printed output by p is:

#<PP:0x81fedf0 @genspace=#<Proc:0x81feda0>, @group_queue=#<PrettyPrint::GroupQueue:0x81fed3c @queue=[[#<PrettyPrint::Group:0x81fed78 @breakables=[], @depth=0, @break=false>], []]>, @buffer=[], @newline="\n", @group_stack=[#<PrettyPrint::Group:0x81fed78 @breakables=[], @depth=0, @break=false>], @buffer_width=0, @indent=0, @maxwidth=79, @output_width=2, @output=#<IO:0x8114ee4>>

pretty-printed output by pp is:

    [[#<PrettyPrint::Group:0x81fed78 @break=false, @breakables=[], @depth=0>],
  [#<PrettyPrint::Group:0x81fed78 @break=false, @breakables=[], @depth=0>],

I like the latter. If you do too, this library is for you.



output obj to +$>+ in pretty printed format.

It returns nil.

Output Customization

To define your customized pretty printing function for your classes, redefine a method pretty_print(pp) in the class. It takes an argument pp which is an instance of the class PP. The method should use PP#text, PP#breakable, PP#nest, PP#group and PP::PPMethods#pp to print the object.


Tanaka Akira <>

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