英文:
Why is String#delete not deleting the `-` char from this string
问题
我试图使用#delete方法清理一些电话号码数据，但根据我的irb测试，只有当我按特定顺序提供参数时，它才会删除'-'字符。
"(941)979- 2000".delete(" -().")仍然保留了-，结果为"941979-2000"
而
"(941)979- 2000".delete(" ()-.")确实移除了-，结果为"9419792000"
我对这个方法参数要求的理解有什么误解？
英文:
I am trying to sanitise some phone number data by using the #delete method, but according to my testing in irb it is only deleting the '-' character when i present it in a certain order in the argument.
"(941)979- 2000".delete(" -().") still returns with the - present; => "941979-2000"
whereas
"(941)979- 2000".delete(" ()-.") does remove the -; => "9419792000"
What is it that I am misunderstanding about this method's argument requirements?
答案1
得分: 2
根据String#delete的文档，Character Selector -(). 表示：
- 在空格和
(之间的任何字符（这包括空格、!、"、#、$、%、&、'和(）或 )或.
也就是说，由这个Character Selector选择的字符集包括空格、!、"、#、$、%、&、'、(、)和.。
而Character Selector ()-. 表示：
- 空格或
(或- 在
)和.之间的任何字符（这包括)、*、+、,、-和.）
也就是说，由这个Character Selector选择的字符集包括空格、(、*、+、,、-和.。
换句话说，第一个Character Selector不选择-字符，因为-不在所选字符集中，而第二个Character Selector选择-字符，因为-在所选字符集中。
在不了解您的具体需求的情况下，我猜想您实际需要的Character Selector可能类似于 \-().、 ()\-.或简单地是 ().-.。
英文:
According to the documentation of String#delete, the Character Selector -(). means:
- ANY character between
((which is!,",#,$,%,&,', and() OR )OR.
I.e. the set of all characters selected by this Character Selector is , !, ", #, $, %, &, ', (, ), and ..
Whereas the Character Selector ()-. means:
(OR- ANY character between
)and.(which is),*,+,,,-, and.)
I.e. the set of all characters selected by this Character Selector is , (, *, +, ,, -, and .
In other words, the first Character Selector does not select the - character because the - is not present in the set of selected characters whereas the second Character Selector does select the - character because the - is present in the set of selected characters.
Without knowing your precise requirements, my guess is that the Character Selector you actually want is something like \-(). or ()\-. or simply ().-.
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