格式化 Ruby 的漂亮打印

发布于01月22日

是否可以更改prettyprint(require 'pp')在格式化输出时使用的宽度？例如:

"mooth"=>["booth", "month", "mooch", "morth", "mouth", "mowth", "sooth", "tooth"]
"morth"=>["forth",
 "mirth",
 "month",
 "mooth",
 "morph",
 "mouth",
 "mowth",
 "north",
 "worth"]

第一个数组是内联打印的，因为它符合prettyprint允许的列宽(79个字符)...第二行被拆分为多行，因为它没有.但我找不到任何方法来更改此行为开始的列.

pp取决于PrettyPrint(它有允许缓冲区不同宽度的方法).有没有办法将默认列宽更改为pp，而不必从头重写(直接访问PrettyPrint)？

或者，是否有类似的ruby gem提供此功能？

推荐答案

#!/usr/bin/ruby1.8

require 'pp'
mooth = [
  "booth", "month", "mooch", "morth",
  "mouth", "mowth", "sooth", "tooth"
]
PP.pp(mooth, $>, 40)
# => ["booth",
# =>  "month",
# =>  "mooch",
# =>  "morth",
# =>  "mouth",
# =>  "mowth",
# =>  "sooth",
# =>  "tooth"]
PP.pp(mooth, $>, 79)
# => ["booth", "month", "mooch", "morth", "mouth", "mowth", "sooth", "tooth"]

要使用猴子补丁更改默认设置，请执行以下操作:

#!/usr/bin/ruby1.8

require 'pp'

class PP
  class << self
    alias_method :old_pp, :pp
    def pp(obj, out = $>, width = 40)
      old_pp(obj, out, width)
    end
  end
end

mooth = ["booth", "month", "mooch", "morth", "mouth", "mowth", "sooth", "tooth"]
pp(mooth)
# => ["booth",
# =>  "month",
# =>  "mooch",
# =>  "morth",
# =>  "mouth",
# =>  "mowth",
# =>  "sooth",
# =>  "tooth"]

这些方法也适用于MRI 1.9.3