ruby - 将字符串拆分为最大字符数的 block 而不打断单词

Question

我想将一个字符串拆分成 block ，每个 block 都在最大字符数内，比如 2000，并且不拆分单词。

我尝试过如下操作:

text.chars.each_slice(2000).map(&:join)

但有时，单词会被拆分。我尝试了一些正则表达式:

text.scan(/.{1,2000}\b|.{1,2000}/).map(&:strip)

来自 this question , 但我不太明白它是如何工作的，它给了我一些不稳定的行为，有时会给出只包含句点的 block 。

任何指点将不胜感激。

Answer 1

代码

def max_groups(str, n)
  arr = []
  pos = 0     
  loop do
    break arr if pos == str.size
    m = str.match(/.{1,#{n}}(?=[ ]|\z)|.{,#{n-1}}[ ]/, pos)
    return nil if m.nil?
    arr << m[0]
    pos += m[0].size
  end
end

示例

str = "Now is the time for all good people to party"
  #    12345678901234567890123456789012345678901234
  #    0         1         2         3         4

max_groups(str, 5)
  #=> nil
max_groups(str, 6)
  #=> ["Now is", " the ", "time ", "for ", "all ", "good ", "people", " to 
max_groups(str, 10)
  #=> ["Now is the", " time for ", "all good ", "people to ", "party"]
max_groups(str, 14)
  #=> ["Now is the ", "time for all ", "good people to", " party"]
max_groups(str, 15)
  #=> ["Now is the time", " for all good ", "people to party"]
max_groups(str, 29)
  #=> ["Now is the time for all good ", "people to party"]
max_groups(str, 43)
  #=> ["Now is the time for all good people to ", "party"]
max_groups(str, 44)
  #=> ["Now is the time for all good people to party"]

str = "How        you do?"
  #    123456789012345678
  #    0         1

max_groups(str, 4)
  #=> ["How ", "    ", "   ", "you ", "do?"]