metaclasses

metaclasses

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• 網絡元類；五分鐘理解元類；元數據類

例句

For instance, it took us a few months to understand how to use metaclasses, but a few years to understand how not to use them.

例如，花幾個月時間就能理解如何使用元類，但是要花幾年時間才能明白如何不使用它們。

We explain the concept of composition of metaclasses.

我們將解釋元類合成的概念。

Of course, the guilt of the authors is obvious here: our earlier installments on metaclasses in Python helped popularize their usage.

當然，作者的過錯也很明顯：我們的關于Python中的元類的前幾部分助長了這種做法的流行。

Each of these metaclasses has attributes from which Class inherits.

這些元類都有Class繼承的屬性。

The metaclasses being extended by the stereotype are specified on the Extensions tab in the Properties view.

元類被原型所擴展，是在屬性視圖Extensions標檢頁完成的。

When you select multiple metaclasses, a generic features window opens where you can change the stereotype.

當您選擇多個元類時，一個通用特性窗口會在您變更模板的地方打開。

Notice that metaclasses were never mentioned in the lookup procedure.

注意，從未在查找過程中提到過元類。

A profile defines a number of stereotype classes that can extend one or more UML metaclasses with additional properties and relationships.

規范定義了許多能夠通過添加屬性和關系被擴展為一個或者更多的UML元類的模板類。

You feel that a custom metaclasses is overkill for the simple job of class initialization, and you would rather use a simpler solution.

您覺得對于類初始化這類簡單的工作使用自定義元類是殺雞用牛刀，所以想要使用一種更為簡單的解決方案。

Just this is the main difference between metaclasses and superclasses.

這正是元類與超類的主要不同。

For metaclasses in Python specifically, Guido van Rossum's essay, Unifying types and classes in Python 2. 2 is useful.

特別是對于Python中的元類，GuidovanRossum的文章UnifyingtypesandclassesinPython2.2也很有用。

Metaclasses are more fragile than many people realize.

元類比很多人認識到的更加脆弱。

Stereotype S1 has two attributes (a1: Integer, and a2 : Boolean), extends Class and Actor metaclasses, and has constraint profileCons1.

StereotypeS1有兩個屬性（a1：整型，以及a2：布爾類形），擴展類和動作元類，并且存在約束profileCons1。

I have some ideas for doing some tricky stuff with metaclasses in future library versions, and I might even work in properties and slots.

對于未來庫版本中的元類，我有幾個技巧方面的想法，而且我甚至可能使用特性和插槽。

Metaclasses defined in the UML 2. 1 metamodel (through metaclass association)

元類定義在UML2.1元類模型中（通過元類的關聯）

If the Duke class should happen to have a custom metaclasses, it can obtain some attributes that way

如果Duke碰巧有一個定制元類，那么它能夠以以下方式獲得一些屬性