class PP
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 $>
in pretty printed format.
It returns obj(s)
.
Output Customization¶ ↑
To define a customized pretty printing function for your classes, redefine method pretty_print(pp) in the class. Note that require 'pp'
is needed before redefining pretty_print(pp).
pretty_print takes the pp
argument, which is an instance of the PP
class. The method uses text
, breakable
, nest
, group
and pp
to print the object.
Pretty-Print JSON
¶ ↑
To pretty-print JSON
refer to JSON#pretty_generate
.
Author¶ ↑
Tanaka Akira <akr@fsij.org>
Constants
- VERSION
-
The version string
Public Class Methods
Source
# File lib/pp.rb, line 96 def PP.pp(obj, out=$>, width=width_for(out)) q = new(out, width) q.guard_inspect_key {q.pp obj} q.flush #$pp = q out << "\n" end
Outputs obj
to out
in pretty printed format of width
columns in width.
If out
is omitted, $>
is assumed. If width
is omitted, the width of out
is assumed (see width_for
).
PP.pp
returns out
.
Source
# File lib/pp.rb, line 125 def sharing_detection Ractor.current[:pp_sharing_detection] end
Returns the sharing detection flag as a boolean value. It is false (nil) by default.
Source
# File lib/pp.rb, line 129 def sharing_detection=(b) Ractor.current[:pp_sharing_detection] = b end
Sets the sharing detection flag to b.
Source
# File lib/pp.rb, line 108 def PP.singleline_pp(obj, out=$>) q = SingleLine.new(out) q.guard_inspect_key {q.pp obj} q.flush out end
Outputs obj
to out
like PP.pp
but with no indent and newline.
PP.singleline_pp
returns out
.
Source
# 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
Returns the usable width for out
. As the width of out
:
-
If
out
is assigned to a tty device, its width is used. -
Otherwise, or it could not get the value, the
COLUMN
environment variable is assumed to be set to the width. -
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.