我可以将 !ATTLIST 功能组合到 DTD 的一行中吗？
我刚刚学习编写 XML 和相关的 DTD，我想知道是否可以将某些内容组合到 !ATTLIST 的一行中。
例如：
我有一个元素 weight，我希望将 (kg|lb) 作为选项，但将 "kg" 设置为默认值。这些都不是必需的，因此状态为#IMPLIED，但我也希望默认权重为“1”。
我可以合法地将所有这些放在一行中吗：
<!ELEMENT weight (#PCDATA)>
<!ATTLIST weight unit CDATA "1" (kg|lb) "kg" #IMPLIED>
或者我可以这样做吗：
<!ELEMENT weight (#PCDATA)>
<!ATTLIST weight unit CDATA>
<!ATTLIST weight unit "1" #IMPLIED>
<!ATTLIST weight unit (kg|lb)>
<!ATTLIST weight unit "kg" #IMPLIED>
我怀疑两者都存在问题，并且我对如何组合这些功能（或者如果我什至可以）感到有点困惑 - 所以我会非常感谢有关正确执行此操作的一些指导。
I am just learning to write XML and associated DTD's, and I'm wondering if I can combine certain things in one line of an !ATTLIST.
eg:
I have an element weight, and I want to have (kg|lb) as options, but set "kg" as the default. None of these are essential, so the status is #IMPLIED, but I also want to have a default weight of "1".
Can I legally put all this in one line:
<!ELEMENT weight (#PCDATA)>
<!ATTLIST weight unit CDATA "1" (kg|lb) "kg" #IMPLIED>
Or can I do it this way:
<!ELEMENT weight (#PCDATA)>
<!ATTLIST weight unit CDATA>
<!ATTLIST weight unit "1" #IMPLIED>
<!ATTLIST weight unit (kg|lb)>
<!ATTLIST weight unit "kg" #IMPLIED>
I suspect there are problems with both, and I am a little confused as to how I combine these features (or if I even can) - so I would really appreciate a little guidance on doing this properly.
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好吧，我已经通过执行以下操作使其正常工作，尽管这可能不是“公认的做法”方式：
我必须将值分解为它自己的属性（现在我想这很有意义），并删除 #暗示，因为我在某处读到通过设置默认值，无论如何它都是暗示的。
希望这对其他人有帮助（假设这是正确的方法）
干杯
Ok, I have got it working by doing the following, although it might not be the 'accepted practice' way:
I had to break the value out into its own attribute (which makes sense now I think about it), and remove the #IMPLIED, since I read somewhere that by setting a default value, its implied anyway.
Hopefully this will help someone else (assuming its the right way to do it)
Cheers