Class: PP

Inherits:
PrettyPrint show all
Includes:
PPMethods
Defined in:
lib/pp.rb

Overview

A pretty-printer for Ruby objects.

What PP Does

Standard output by #p returns this:

#<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 returns this:

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

Usage

pp(obj)             #=> obj
pp obj              #=> obj
pp(obj1, obj2, ...) #=> [obj1, obj2, ...]
pp()                #=> nil

Output obj(s) to $> in pretty printed format.

It returns obj(s).

Output Customization

To define a customized pretty printing function for your classes, redefine method #pretty_print(pp) in the class. Note that require 'pp' is needed before redefining #pretty_print(pp).

#pretty_print takes the pp argument, which is an instance of the PP class. The method uses #text, #breakable, #nest, #group and #pp to print the object.

Pretty-Print JSON

To pretty-print JSON refer to JSON#pretty_generate.

Author

Tanaka Akira <[email protected]>

Defined Under Namespace

Modules: ObjectMixin, PPMethods Classes: SingleLine

Constant Summary collapse

VERSION =

The version string

"0.6.2"

Class Attribute Summary collapse

Class Method Summary collapse

Methods included from PPMethods

#check_inspect_key, #comma_breakable, #guard_inspect_key, #object_address_group, #object_group, #pop_inspect_key, #pp, #pp_hash, #pp_hash_pair, #pp_object, #push_inspect_key, #seplist

Class Attribute Details

.sharing_detection ⇒ Object

Returns the sharing detection flag as a boolean value. It is false by default.



125
126
127
 
# File 'lib/pp.rb', line 125

def sharing_detection
  Ractor.current[:pp_sharing_detection]
end

Class Method Details

.mcall(obj, mod, meth, *args, &block) ⇒ Object

:stopdoc:



116
117
118
 
# File 'lib/pp.rb', line 116

def PP.mcall(obj, mod, meth, *args, &block)
  mod.instance_method(meth).bind_call(obj, *args, &block)
end

.pp(obj, out = $>, width = width_for(out)) ⇒ Object

Outputs obj to out in pretty printed format of width columns in width.

If out is omitted, $> is assumed. If width is omitted, the width of out is assumed (see width_for).

PP.pp returns out.



96
97
98
99
100
101
102
 
# File 'lib/pp.rb', line 96

def PP.pp(obj, out=$>, width=width_for(out))
  q = new(out, width)
  q.guard_inspect_key {q.pp obj}
  q.flush
  #$pp = q
  out << "\n"
end

.singleline_pp(obj, out = $>) ⇒ Object

Outputs obj to out like PP.pp but with no indent and newline.

PP.singleline_pp returns out.



108
109
110
111
112
113
 
# File 'lib/pp.rb', line 108

def PP.singleline_pp(obj, out=$>)
  q = SingleLine.new(out)
  q.guard_inspect_key {q.pp obj}
  q.flush
  out
end

.width_for(out) ⇒ Object

Returns the usable width for out. As the width of out:

  1. If out is assigned to a tty device, its width is used.

  2. Otherwise, or it could not get the value, the COLUMN environment variable is assumed to be set to the width.

  3. If COLUMN is not set to a non-zero number, 80 is assumed.

And finally, returns the above width value - 1.

  • This -1 is for Windows command prompt, which moves the cursor to the next line if it reaches the last column.



79
80
81
82
83
84
85
86
 
# File 'lib/pp.rb', line 79

def PP.width_for(out)
  begin
    require 'io/console'
    _, width = out.winsize
  rescue LoadError, NoMethodError, SystemCallError
  end
  (width || ENV['COLUMNS']&.to_i&.nonzero? || 80) - 1
end