什麼是包含撇號的Ruby正則表達式？

Question

我目前正在爲Ruby做一個練習，並且無法通過最後的測試。最後一次測試讀取：

def test_with_apostrophes 
    phrase = Phrase.new("First: don't laugh. Then: don't cry.") 
    counts = {"first"=>1, "don't"=>2, "laugh"=>1, "then"=>1, "cry"=>1} 
    assert_equal counts, phrase.word_count 
end 

錯誤我收到的是：

1) Failure: 
PhraseTest#test_with_apostrophes [word_count_test.rb:61]: 
--- expected 
+++ actual 
@@ -1 +1 @@ 
-{"first"=>1, "don't"=>2, "laugh"=>1, "then"=>1, "cry"=>1} 
+{"first"=>1, "don"=>2, "t"=>2, "laugh"=>1, "then"=>1, "cry"=>1} 

我當前的代碼是：

class Phrase 
    attr_reader :input 

    def initialize(input) 
    @input = input 
    end 

    def word_count 
    count = {} 
    splitted = input.downcase.scan(/\w+/) 
    splitted.each do | word | 
    if !count.key?(word) 
    count[word] = 1 
    else 
    count[word] = count[word] + 1 
    end 
    end 
    count 
end 
end 

什麼是正則表達式，包括撇號？

Answer 1

您想要使用「字符類」，如http://www.regular-expressions.info/charclass.html中所述。

所以，與其\w+，您可以使用[\w']+，它說你想要一個或多個要麼單詞字符或撇號。

Answer 2

嘗試：

splitted = input.downcase.scan(/[\w-']+/) 

Answer 3

試試這個讓你的話的頻率，

words_freq = Hash.new(0) 

"First: don't laugh. Then: don't cry.".split(/\s+/).each { |word| words_freq[word.downcase.delete(':|.')] += 1 } 

給#words_freq = {"first"=>1, "don't"=>2, "laugh"=>1, "then"=>1, "cry"=>1}