# Copyright (C) 2001 Python Software Foundation

# This file is distributed under the same license as the Python package.

#

# Translators:

# Liang-Bo Wang <[email protected]>, 2015

# Liang-Bo Wang <[email protected]>, 2016

# hsiao yi <[email protected]>, 2015

# Steven Hsu <[email protected]>, 2021-2022

msgid ""

msgstr ""

"Project-Id-Version: Python 3.14\n"

"Report-Msgid-Bugs-To: \n"

"POT-Creation-Date: 2026-02-18 00:20+0000\n"

"PO-Revision-Date: 2022-07-24 14:52+0800\n"

"Last-Translator: Steven Hsu <[email protected]>\n"

"Language-Team: Chinese - TAIWAN (https://github.com/python/python-docs-zh-"

"tw)\n"

"Language: zh_TW\n"

"MIME-Version: 1.0\n"

"Content-Type: text/plain; charset=UTF-8\n"

"Content-Transfer-Encoding: 8bit\n"

"Plural-Forms: nplurals=1; plural=0;\n"

"X-Generator: Poedit 3.1.1\n"

#: ../../tutorial/controlflow.rst:5

msgid "More Control Flow Tools"

msgstr "深入了解流程控制"

#: ../../tutorial/controlflow.rst:7

msgid ""

"As well as the :keyword:`while` statement just introduced, Python uses a few "

"more that we will encounter in this chapter."

msgstr ""

"除了剛才介紹的 :keyword:`while`，這章節還會介紹一些 Python 的陳述式語法。"

#: ../../tutorial/controlflow.rst:14

msgid ":keyword:`!if` Statements"

msgstr ":keyword:`!if` 陳述式"

#: ../../tutorial/controlflow.rst:16

msgid ""

"Perhaps the most well-known statement type is the :keyword:`if` statement. "

"For example::"

msgstr "或許最常見的陳述式種類就是 :keyword:`if` 了。舉例來說： ::"

#: ../../tutorial/controlflow.rst:19

msgid ""

">>> x = int(input(\"Please enter an integer: \"))\n"

"Please enter an integer: 42\n"

">>> if x < 0:\n"

"... x = 0\n"

"... print('Negative changed to zero')\n"

"... elif x == 0:\n"

"... print('Zero')\n"

"... elif x == 1:\n"

"... print('Single')\n"

"... else:\n"

"... print('More')\n"

"...\n"

"More"

msgstr ""

">>> x = int(input(\"Please enter an integer: \"))\n"

"Please enter an integer: 42\n"

">>> if x < 0:\n"

"... x = 0\n"

"... print('Negative changed to zero')\n"

"... elif x == 0:\n"

"... print('Zero')\n"

"... elif x == 1:\n"

"... print('Single')\n"

"... else:\n"

"... print('More')\n"

"...\n"

"More"

#: ../../tutorial/controlflow.rst:33

msgid ""

"There can be zero or more :keyword:`elif` parts, and the :keyword:`else` "

"part is optional. The keyword ':keyword:`!elif`' is short for 'else if', "

"and is useful to avoid excessive indentation. An :keyword:`!if` ... :"

"keyword:`!elif` ... :keyword:`!elif` ... sequence is a substitute for the "

"``switch`` or ``case`` statements found in other languages."

msgstr ""

"在陳述式中，可以沒有或有許多個 :keyword:`elif` 敘述，且 :keyword:`else` 敘述"

"並不是必要的。關鍵字 :keyword:`!elif` 是「else if」的縮寫，用來避免過多的縮"

"排。一個 :keyword:`!if` ... :keyword:`!elif` ... :keyword:`!elif` ... 序列可"

"以用來替代其他程式語言中的 ``switch`` 或 ``case`` 陳述式。"

#: ../../tutorial/controlflow.rst:39

msgid ""

"If you're comparing the same value to several constants, or checking for "

"specific types or attributes, you may also find the :keyword:`!match` "

"statement useful. For more details see :ref:`tut-match`."

msgstr ""

"如果你要將同一個值與多個常數進行比較，或者檢查特定的型別或屬性，你可能會發"

"現 :keyword:`!match` 陳述式也很有用。更多的細節，請參閱 :ref:`tut-match`。"

#: ../../tutorial/controlflow.rst:46

msgid ":keyword:`!for` Statements"

msgstr ":keyword:`!for` 陳述式"

#: ../../tutorial/controlflow.rst:51

msgid ""

"The :keyword:`for` statement in Python differs a bit from what you may be "

"used to in C or Pascal. Rather than always iterating over an arithmetic "

"progression of numbers (like in Pascal), or giving the user the ability to "

"define both the iteration step and halting condition (as C), Python's :"

"keyword:`!for` statement iterates over the items of any sequence (a list or "

"a string), in the order that they appear in the sequence. For example (no "

"pun intended):"

msgstr ""

"在 Python 中的 :keyword:`for` 陳述式有點不同於在 C 或 Pascal 中的慣用方式。相"

"較於只能疊代 (iterate) 一個等差數列（如 Pascal），或給予使用者定義疊代步驟與"

"終止條件（如 C），Python 的 :keyword:`!for` 陳述式疊代任何序列（list 或者字"

"串）的元素，順序與它們出現在序列中的順序相同。例如（無意雙關）： ::"

#: ../../tutorial/controlflow.rst:63

msgid ""

">>> # Measure some strings:\n"

">>> words = ['cat', 'window', 'defenestrate']\n"

">>> for w in words:\n"

"... print(w, len(w))\n"

"...\n"

"cat 3\n"

"window 6\n"

"defenestrate 12"

msgstr ""

">>> # 測量一些字串：\n"

">>> words = ['cat', 'window', 'defenestrate']\n"

">>> for w in words:\n"

"... print(w, len(w))\n"

"...\n"

"cat 3\n"

"window 6\n"

"defenestrate 12"

#: ../../tutorial/controlflow.rst:72

msgid ""

"Code that modifies a collection while iterating over that same collection "

"can be tricky to get right. Instead, it is usually more straight-forward to "

"loop over a copy of the collection or to create a new collection::"

msgstr ""

"在疊代一個集合的同時修改該集合的內容，很難取得想要的結果。比較直觀的替代方"

"式，是疊代該集合的副本，或建立一個新的集合： ::"

#: ../../tutorial/controlflow.rst:76

msgid ""

"# Create a sample collection\n"

"users = {'Hans': 'active', 'Éléonore': 'inactive', '景太郎': 'active'}\n"

"\n"

"# Strategy: Iterate over a copy\n"

"for user, status in users.copy().items():\n"

" if status == 'inactive':\n"

" del users[user]\n"

"\n"

"# Strategy: Create a new collection\n"

"active_users = {}\n"

"for user, status in users.items():\n"

" if status == 'active':\n"

" active_users[user] = status"

msgstr ""

"# 建立一個範例集合\n"

"users = {'Hans': 'active', 'Éléonore': 'inactive', '景太郎': 'active'}\n"

"\n"

"# 策略：對副本進行疊代\n"

"for user, status in users.copy().items():\n"

" if status == 'inactive':\n"

" del users[user]\n"

"\n"

"# 策略：建立一個新集合\n"

"active_users = {}\n"

"for user, status in users.items():\n"

" if status == 'active':\n"

" active_users[user] = status"

#: ../../tutorial/controlflow.rst:94

msgid "The :func:`range` Function"

msgstr ":func:`range` 函式"

#: ../../tutorial/controlflow.rst:96

msgid ""

"If you do need to iterate over a sequence of numbers, the built-in function :"

"func:`range` comes in handy. It generates arithmetic progressions::"

msgstr ""

"如果你需要疊代一個數列的話，使用內建 :func:`range` 函式就很方便。它可以生成一"

"等差數列： ::"

#: ../../tutorial/controlflow.rst:99

msgid ""

">>> for i in range(5):\n"

"... print(i)\n"

"...\n"

"0\n"

"1\n"

"2\n"

"3\n"

"4"

msgstr ""

">>> for i in range(5):\n"

"... print(i)\n"

"...\n"

"0\n"

"1\n"

"2\n"

"3\n"

"4"

#: ../../tutorial/controlflow.rst:108

msgid ""

"The given end point is never part of the generated sequence; ``range(10)`` "

"generates 10 values, the legal indices for items of a sequence of length "

"10. It is possible to let the range start at another number, or to specify "

"a different increment (even negative; sometimes this is called the 'step')::"

msgstr ""

"給定的結束值永遠不會出現在生成的序列中；``range(10)`` 生成的 10 個數值，即對"

"應存取一個長度為 10 的序列內每一個項目的索引值。也可以讓 range 從其他數值開始"

"計數，或者給定不同的公差（甚至為負；有時稱之為 step）： ::"

#: ../../tutorial/controlflow.rst:113

msgid ""

">>> list(range(5, 10))\n"

"[5, 6, 7, 8, 9]\n"

"\n"

">>> list(range(0, 10, 3))\n"

"[0, 3, 6, 9]\n"

"\n"

">>> list(range(-10, -100, -30))\n"

"[-10, -40, -70]"

msgstr ""

">>> list(range(5, 10))\n"

"[5, 6, 7, 8, 9]\n"

"\n"

">>> list(range(0, 10, 3))\n"

"[0, 3, 6, 9]\n"

"\n"

">>> list(range(-10, -100, -30))\n"

"[-10, -40, -70]"

#: ../../tutorial/controlflow.rst:122

msgid ""

"To iterate over the indices of a sequence, you can combine :func:`range` "

"and :func:`len` as follows::"

msgstr ""

"欲疊代一個序列的索引值，你可以搭配使用 :func:`range` 和 :func:`len` 如下： ::"

#: ../../tutorial/controlflow.rst:125

msgid ""

">>> a = ['Mary', 'had', 'a', 'little', 'lamb']\n"

">>> for i in range(len(a)):\n"

"... print(i, a[i])\n"

"...\n"

"0 Mary\n"

"1 had\n"

"2 a\n"

"3 little\n"

"4 lamb"

msgstr ""

">>> a = ['Mary', 'had', 'a', 'little', 'lamb']\n"

">>> for i in range(len(a)):\n"

"... print(i, a[i])\n"

"...\n"

"0 Mary\n"

"1 had\n"

"2 a\n"

"3 little\n"

"4 lamb"

#: ../../tutorial/controlflow.rst:135

msgid ""

"In most such cases, however, it is convenient to use the :func:`enumerate` "

"function, see :ref:`tut-loopidioms`."

msgstr ""

"然而，在多數的情況，使用 :func:`enumerate` 函式將更為方便，詳見\\ :ref:`tut-"

"loopidioms`。"

#: ../../tutorial/controlflow.rst:138

msgid "A strange thing happens if you just print a range::"

msgstr "如果直接印出一個 range 則會出現奇怪的輸出： ::"

#: ../../tutorial/controlflow.rst:140

msgid ""

">>> range(10)\n"

"range(0, 10)"

msgstr ""

">>> range(10)\n"

"range(0, 10)"

#: ../../tutorial/controlflow.rst:143

msgid ""

"In many ways the object returned by :func:`range` behaves as if it is a "

"list, but in fact it isn't. It is an object which returns the successive "

"items of the desired sequence when you iterate over it, but it doesn't "

"really make the list, thus saving space."

msgstr ""

"在很多情況下，由 :func:`range` 回傳的物件表現得像是一個 list（串列）一樣，但"

"實際上它並不是。它是一個在疊代時能夠回傳所要求的序列中所有項目的物件，但它不"

"會真正建出這個序列的 list，以節省空間。"

#: ../../tutorial/controlflow.rst:148

msgid ""

"We say such an object is :term:`iterable`, that is, suitable as a target for "

"functions and constructs that expect something from which they can obtain "

"successive items until the supply is exhausted. We have seen that the :"

"keyword:`for` statement is such a construct, while an example of a function "

"that takes an iterable is :func:`sum`::"

msgstr ""

"我們稱這樣的物件為 :term:`iterable`\\ （可疊代物件），意即能作為函式及架構中"

"可以一直取得項目直到取盡的對象。我們已經了解 :keyword:`for` 陳述式就是如此的"

"架構，另一個使用 iterable 的函式範例是 :func:`sum`： ::"

#: ../../tutorial/controlflow.rst:154

msgid ""

">>> sum(range(4)) # 0 + 1 + 2 + 3\n"

"6"

msgstr ""

">>> sum(range(4)) # 0 + 1 + 2 + 3\n"

"6"

#: ../../tutorial/controlflow.rst:157

msgid ""

"Later we will see more functions that return iterables and take iterables as "

"arguments. In chapter :ref:`tut-structures`, we will discuss :func:`list` "

"in more detail."

msgstr ""

"待會我們可以看到更多回傳 iterable 和使用 iterable 為引數的函式。在\\ :ref:"

"`tut-structures`\\ 章節中，我們會討論更多關於 :func:`list` 的細節。"

#: ../../tutorial/controlflow.rst:164

msgid ":keyword:`!break` and :keyword:`!continue` Statements"

msgstr ":keyword:`!break` 和 :keyword:`!continue` 陳述式"

#: ../../tutorial/controlflow.rst:166

msgid ""

"The :keyword:`break` statement breaks out of the innermost enclosing :"

"keyword:`for` or :keyword:`while` loop::"

msgstr ""

":keyword:`break` 陳述式，終止包含它的最內部 :keyword:`for` 或 :keyword:"

"`while` 迴圈： ::"

#: ../../tutorial/controlflow.rst:169

msgid ""

">>> for n in range(2, 10):\n"

"... for x in range(2, n):\n"

"... if n % x == 0:\n"

"... print(f\"{n} equals {x} * {n//x}\")\n"

"... break\n"

"...\n"

"4 equals 2 * 2\n"

"6 equals 2 * 3\n"

"8 equals 2 * 4\n"

"9 equals 3 * 3"

msgstr ""

">>> for n in range(2, 10):\n"

"... for x in range(2, n):\n"

"... if n % x == 0:\n"

"... print(f\"{n} equals {x} * {n//x}\")\n"

"... break\n"

"...\n"

"4 equals 2 * 2\n"

"6 equals 2 * 3\n"

"8 equals 2 * 4\n"

"9 equals 3 * 3"

#: ../../tutorial/controlflow.rst:180

msgid ""

"The :keyword:`continue` statement continues with the next iteration of the "

"loop::"

msgstr ":keyword:`continue` 陳述式讓所屬的迴圈繼續執行下個疊代： ::"

#: ../../tutorial/controlflow.rst:183

msgid ""

">>> for num in range(2, 10):\n"

"... if num % 2 == 0:\n"

"... print(f\"Found an even number {num}\")\n"

"... continue\n"

"... print(f\"Found an odd number {num}\")\n"

"...\n"

"Found an even number 2\n"

"Found an odd number 3\n"

"Found an even number 4\n"

"Found an odd number 5\n"

"Found an even number 6\n"

"Found an odd number 7\n"

"Found an even number 8\n"

"Found an odd number 9"

msgstr ""

">>> for num in range(2, 10):\n"

"... if num % 2 == 0:\n"

"... print(f\"Found an even number {num}\")\n"

"... continue\n"

"... print(f\"Found an odd number {num}\")\n"

"...\n"

"Found an even number 2\n"

"Found an odd number 3\n"

"Found an even number 4\n"

"Found an odd number 5\n"

"Found an even number 6\n"

"Found an odd number 7\n"

"Found an even number 8\n"

"Found an odd number 9"

#: ../../tutorial/controlflow.rst:202

msgid ":keyword:`!else` Clauses on Loops"

msgstr "迴圈的 :keyword:`!else` 子句"

#: ../../tutorial/controlflow.rst:204

msgid ""

"In a :keyword:`!for` or :keyword:`!while` loop the :keyword:`!break` "

"statement may be paired with an :keyword:`!else` clause. If the loop "

"finishes without executing the :keyword:`!break`, the :keyword:`!else` "

"clause executes."

msgstr ""

"在 :keyword:`!for` 或 :keyword:`!while` 迴圈中，:keyword:`!break` 陳述句可能"

"與 :keyword:`!else` 子句配對。如果迴圈完成而沒有執行 :keyword:`!break`，:"

"keyword:`!else` 子句會被執行。"

#: ../../tutorial/controlflow.rst:208

msgid ""

"In a :keyword:`for` loop, the :keyword:`!else` clause is executed after the "

"loop finishes its final iteration, that is, if no break occurred."

msgstr ""

"在 :keyword:`for` 迴圈中，:keyword:`!else` 子句會在迴圈完成最終的疊代後執行。"

#: ../../tutorial/controlflow.rst:211

msgid ""

"In a :keyword:`while` loop, it's executed after the loop's condition becomes "

"false."

msgstr "在 :keyword:`while` 迴圈中，它會在迴圈條件變為 false 後執行。"

#: ../../tutorial/controlflow.rst:213

msgid ""

"In either kind of loop, the :keyword:`!else` clause is **not** executed if "

"the loop was terminated by a :keyword:`break`. Of course, other ways of "

"ending the loop early, such as a :keyword:`return` or a raised exception, "

"will also skip execution of the :keyword:`else` clause."

msgstr ""

"在任何一種迴圈中，如果迴圈由 :keyword:`break` 終止，則不會執行 :keyword:`!"

"else` 子句。當然其他提早結束迴圈的方式（例如 :keyword:`return` 或引發例外）也"

"會跳過 :keyword:`else` 子句的執行。"

#: ../../tutorial/controlflow.rst:218

msgid ""

"This is exemplified in the following :keyword:`!for` loop, which searches "

"for prime numbers::"

msgstr "下面的 :keyword:`!for` 迴圈對此進行了舉例說明，該迴圈用以搜尋質數： ::"

#: ../../tutorial/controlflow.rst:221

msgid ""

">>> for n in range(2, 10):\n"

"... for x in range(2, n):\n"

"... if n % x == 0:\n"

"... print(n, 'equals', x, '*', n//x)\n"

"... break\n"

"... else:\n"

"... # loop fell through without finding a factor\n"

"... print(n, 'is a prime number')\n"

"...\n"

"2 is a prime number\n"

"3 is a prime number\n"

"4 equals 2 * 2\n"

"5 is a prime number\n"

"6 equals 2 * 3\n"

"7 is a prime number\n"

"8 equals 2 * 4\n"

"9 equals 3 * 3"

msgstr ""

">>> for n in range(2, 10):\n"

"... for x in range(2, n):\n"

"... if n % x == 0:\n"

"... print(n, 'equals', x, '*', n//x)\n"

"... break\n"

"... else:\n"

"... # 迴圈結束但沒有找到因數\n"

"... print(n, 'is a prime number')\n"

"...\n"

"2 is a prime number\n"

"3 is a prime number\n"

"4 equals 2 * 2\n"

"5 is a prime number\n"

"6 equals 2 * 3\n"

"7 is a prime number\n"

"8 equals 2 * 4\n"

"9 equals 3 * 3"

#: ../../tutorial/controlflow.rst:239

msgid ""

"(Yes, this is the correct code. Look closely: the ``else`` clause belongs "

"to the ``for`` loop, **not** the ``if`` statement.)"

msgstr ""

"（沒錯，這是正確的程式碼。請看仔細：``else`` 子句屬於 ``for`` 迴圈，**並非** "

"``if`` 陳述式。）"

#: ../../tutorial/controlflow.rst:242

msgid ""

"One way to think of the else clause is to imagine it paired with the ``if`` "

"inside the loop. As the loop executes, it will run a sequence like if/if/if/"

"else. The ``if`` is inside the loop, encountered a number of times. If the "

"condition is ever true, a ``break`` will happen. If the condition is never "

"true, the ``else`` clause outside the loop will execute."

msgstr ""

"理解 else 子句的一個方法是將它想像成與迴圈內的 ``if`` 配對。當迴圈執行時，它"

"會運行如 if/if/if/else 的序列。``if`` 在迴圈內，會遇到多次。如果條件曾經為"

"真，``break`` 就會發生。如果條件從未為真，迴圈外的 ``else`` 子句就會執行。"

#: ../../tutorial/controlflow.rst:248

msgid ""

"When used with a loop, the ``else`` clause has more in common with the "

"``else`` clause of a :keyword:`try` statement than it does with that of "

"``if`` statements: a ``try`` statement's ``else`` clause runs when no "

"exception occurs, and a loop's ``else`` clause runs when no ``break`` "

"occurs. For more on the ``try`` statement and exceptions, see :ref:`tut-"

"handling`."

msgstr ""

"當 ``else`` 子句用於迴圈時，相較於搭配 ``if`` 陳述式使用，它的行為與 :"

"keyword:`try` 陳述式中的 ``else`` 子句更為相似：``try`` 陳述式的 ``else`` 子"

"句在沒有發生例外 (exception) 時執行，而迴圈的 ``else`` 子句在沒有任何 "

"``break`` 發生時執行。更多有關 ``try`` 陳述式和例外的介紹，見\\ :ref:`tut-"

"handling`。"

#: ../../tutorial/controlflow.rst:258

msgid ":keyword:`!pass` Statements"

msgstr ":keyword:`!pass` 陳述式"

#: ../../tutorial/controlflow.rst:260

msgid ""

"The :keyword:`pass` statement does nothing. It can be used when a statement "

"is required syntactically but the program requires no action. For example::"

msgstr ""

":keyword:`pass` 陳述式不執行任何動作。它可用在語法上需要一個陳述式但程式不需"

"要執行任何動作的時候。例如： ::"

#: ../../tutorial/controlflow.rst:263

msgid ""

">>> while True:\n"

"... pass # Busy-wait for keyboard interrupt (Ctrl+C)\n"

"..."

msgstr ""

">>> while True:\n"

"... pass # 忙碌等待鍵盤中斷 (Ctrl+C)\n"

"..."

#: ../../tutorial/controlflow.rst:267

msgid "This is commonly used for creating minimal classes::"

msgstr "這經常用於建立簡單的 class（類別）： ::"

#: ../../tutorial/controlflow.rst:269

msgid ""

">>> class MyEmptyClass:\n"

"... pass\n"

"..."

msgstr ""

">>> class MyEmptyClass:\n"

"... pass\n"

"..."

#: ../../tutorial/controlflow.rst:273

msgid ""

"Another place :keyword:`pass` can be used is as a place-holder for a "

"function or conditional body when you are working on new code, allowing you "

"to keep thinking at a more abstract level. The :keyword:`!pass` is silently "

"ignored::"

msgstr ""

":keyword:`pass` 亦可作為一個函式或條件判斷主體的預留位置，在你撰寫新的程式碼"

"時讓你保持在更抽象的思維層次。:keyword:`!pass` 會直接被忽略： ::"

#: ../../tutorial/controlflow.rst:277

msgid ""

">>> def initlog(*args):\n"

"... pass # Remember to implement this!\n"

"..."

msgstr ""

">>> def initlog(*args):\n"

"... pass # 記得要實作這個！\n"

"..."

#: ../../tutorial/controlflow.rst:281

msgid ""

"For this last case, many people use the ellipsis literal :code:`...` instead "

"of :code:`pass`. This use has no special meaning to Python, and is not part "

"of the language definition (you could use any constant expression here), "

"but :code:`...` is used conventionally as a placeholder body as well. See :"

"ref:`bltin-ellipsis-object`."

msgstr ""

"在最後這個例子中，許多人會使用刪節號字面值 :code:`...` 來取代 :code:`pass`。"

"這種用法對 Python 並沒有特殊的意義，且並非語言定義的一部分（你也可以在這裡使"

"用任何常數運算式），但 :code:`...` 也慣例上被用作預留主體 (placeholder "

"body)。見 :ref:`bltin-ellipsis-object`。"

#: ../../tutorial/controlflow.rst:291

msgid ":keyword:`!match` Statements"

msgstr ":keyword:`!match` 陳述式"

#: ../../tutorial/controlflow.rst:293

msgid ""

"A :keyword:`match` statement takes an expression and compares its value to "

"successive patterns given as one or more case blocks. This is superficially "

"similar to a switch statement in C, Java or JavaScript (and many other "

"languages), but it's more similar to pattern matching in languages like Rust "

"or Haskell. Only the first pattern that matches gets executed and it can "

"also extract components (sequence elements or object attributes) from the "

"value into variables. If no case matches, none of the branches is executed."

msgstr ""

":keyword:`match` 陳述式會拿取一個運算式，並將其值與多個連續的模式 (pattern) "

"進行比較，這些模式是以一個或多個 case 區塊來表示。表面上，這類似 C、Java 或 "

"JavaScript（以及許多其他語言）中的 switch 陳述式，但它與 Rust 或 Haskell 等語"

"言中的模式匹配 (pattern matching) 更為相近。只有第一個匹配成功的模式會被執"

"行，而它也可以將成分（序列元素或物件屬性）從值中提取到變數中。如果沒有任何的 "

"case 匹配成功，則不會執行任何的分支。"

#: ../../tutorial/controlflow.rst:302

msgid ""

"The simplest form compares a subject value against one or more literals::"

msgstr ""

"最簡單的形式，是將一個主題值 (subject value) 與一個或多個字面值 (literal) 進"

"行比較： ::"

#: ../../tutorial/controlflow.rst:304

msgid ""

"def http_error(status):\n"

" match status:\n"

" case 400:\n"

" return \"Bad request\"\n"

" case 404:\n"

" return \"Not found\"\n"

" case 418:\n"

" return \"I'm a teapot\"\n"

" case _:\n"

" return \"Something's wrong with the internet\""

msgstr ""

"def http_error(status):\n"

" match status:\n"

" case 400:\n"

" return \"Bad request\"\n"

" case 404:\n"

" return \"Not found\"\n"

" case 418:\n"

" return \"I'm a teapot\"\n"

" case _:\n"

" return \"Something's wrong with the internet\""

#: ../../tutorial/controlflow.rst:315

msgid ""

"Note the last block: the \"variable name\" ``_`` acts as a *wildcard* and "

"never fails to match."

msgstr ""

"請注意最後一段：「變數名稱」\\ ``_`` 是作為\\ *通用字元 (wildcard)*\\ 的角"

"色，且永遠不會匹配失敗。"

#: ../../tutorial/controlflow.rst:318

msgid ""

"You can combine several literals in a single pattern using ``|`` (\"or\")::"

msgstr "你可以使用 ``|``\\ （「或」）來將多個字面值組合在單一模式中： ::"

#: ../../tutorial/controlflow.rst:320

msgid ""

"case 401 | 403 | 404:\n"

" return \"Not allowed\""

msgstr ""

"case 401 | 403 | 404:\n"

" return \"Not allowed\""

#: ../../tutorial/controlflow.rst:323

msgid ""

"Patterns can look like unpacking assignments, and can be used to bind "

"variables::"

msgstr ""

"模式可以看起來像是拆解賦值 (unpacking assignment)，且可以用來連結變數： ::"

#: ../../tutorial/controlflow.rst:326

msgid ""

"# point is an (x, y) tuple\n"

"match point:\n"

" case (0, 0):\n"

" print(\"Origin\")\n"

" case (0, y):\n"

" print(f\"Y={y}\")\n"

" case (x, 0):\n"

" print(f\"X={x}\")\n"

" case (x, y):\n"

" print(f\"X={x}, Y={y}\")\n"

" case _:\n"

" raise ValueError(\"Not a point\")"

msgstr ""

"# point 是一個 (x, y) 元組\n"

"match point:\n"

" case (0, 0):\n"

" print(\"Origin\")\n"

" case (0, y):\n"

" print(f\"Y={y}\")\n"

" case (x, 0):\n"

" print(f\"X={x}\")\n"

" case (x, y):\n"

" print(f\"X={x}, Y={y}\")\n"

" case _:\n"

" raise ValueError(\"Not a point\")"

#: ../../tutorial/controlflow.rst:339

msgid ""

"Study that one carefully! The first pattern has two literals, and can be "

"thought of as an extension of the literal pattern shown above. But the next "

"two patterns combine a literal and a variable, and the variable *binds* a "

"value from the subject (``point``). The fourth pattern captures two values, "

"which makes it conceptually similar to the unpacking assignment ``(x, y) = "

"point``."

msgstr ""

"請仔細研究那個例子！第一個模式有兩個字面值，可以想作是之前所述的字面值模式的"

"延伸。但是接下來的兩個模式結合了一個字面值和一個變數，且該變數\\ *繫結 "

"(bind)* 了來自主題 (``point``) 的一個值。第四個模式會擷取兩個值，這使得它在概"

"念上類似於拆解賦值 ``(x, y) = point``。"

#: ../../tutorial/controlflow.rst:346

msgid ""

"If you are using classes to structure your data you can use the class name "

"followed by an argument list resembling a constructor, but with the ability "

"to capture attributes into variables::"

msgstr ""

"如果你要用 class 來結構化你的資料，你可以使用該 class 的名稱加上一個引數列"

"表，類似一個建構式 (constructor)，但它能夠將屬性擷取到變數中： ::"

#: ../../tutorial/controlflow.rst:350

msgid ""

"class Point:\n"

" def __init__(self, x, y):\n"

" self.x = x\n"

" self.y = y\n"

"\n"

"def where_is(point):\n"

" match point:\n"

" case Point(x=0, y=0):\n"

" print(\"Origin\")\n"

" case Point(x=0, y=y):\n"

" print(f\"Y={y}\")\n"

" case Point(x=x, y=0):\n"

" print(f\"X={x}\")\n"

" case Point():\n"

" print(\"Somewhere else\")\n"

" case _:\n"

" print(\"Not a point\")"

msgstr ""

"class Point:\n"

" def __init__(self, x, y):\n"

" self.x = x\n"

" self.y = y\n"

"\n"

"def where_is(point):\n"

" match point:\n"

" case Point(x=0, y=0):\n"

" print(\"Origin\")\n"

" case Point(x=0, y=y):\n"

" print(f\"Y={y}\")\n"

" case Point(x=x, y=0):\n"

" print(f\"X={x}\")\n"

" case Point():\n"

" print(\"Somewhere else\")\n"

" case _:\n"

" print(\"Not a point\")"

#: ../../tutorial/controlflow.rst:368

msgid ""

"You can use positional parameters with some builtin classes that provide an "

"ordering for their attributes (e.g. dataclasses). You can also define a "

"specific position for attributes in patterns by setting the "

"``__match_args__`` special attribute in your classes. If it's set to (\"x\", "

"\"y\"), the following patterns are all equivalent (and all bind the ``y`` "

"attribute to the ``var`` variable)::"

msgstr ""

"你可以將位置參數 (positional parameter) 與一些能夠排序其屬性的內建 class（例"

"如 dataclasses）一起使用。你也可以透過在 class 中設定特殊屬性 "

"``__match_args__``，來定義模式中屬性們的特定位置。如果它被設定為 (\"x\", "

"\"y\")，則以下的模式都是等價的（且都會將屬性 ``y`` 連結到變數 ``var``）： ::"

#: ../../tutorial/controlflow.rst:374

msgid ""

"Point(1, var)\n"

"Point(1, y=var)\n"

"Point(x=1, y=var)\n"

"Point(y=var, x=1)"

msgstr ""

"Point(1, var)\n"

"Point(1, y=var)\n"

"Point(x=1, y=var)\n"

"Point(y=var, x=1)"

#: ../../tutorial/controlflow.rst:379

msgid ""

"A recommended way to read patterns is to look at them as an extended form of "

"what you would put on the left of an assignment, to understand which "

"variables would be set to what. Only the standalone names (like ``var`` "

"above) are assigned to by a match statement. Dotted names (like ``foo."

"bar``), attribute names (the ``x=`` and ``y=`` above) or class names "

"(recognized by the \"(...)\" next to them like ``Point`` above) are never "

"assigned to."

msgstr ""

"理解模式的一種推薦方法，是將它們看作是你會放在賦值 (assignment) 左側內容的一"

"種延伸形式，這樣就可以了解哪些變數會被設為何值。只有獨立的名稱（像是上面的 "

"``var``）能被 match 陳述式賦值。點分隔名稱（如 ``foo.bar``）、屬性名稱（上面"

"的 ``x=`` 及 ``y=``）或 class 名稱（由它們後面的 \"(...)\" 被辨識，如上面的 "

"``Point``）則永遠無法被賦值。"

#: ../../tutorial/controlflow.rst:386

msgid ""

"Patterns can be arbitrarily nested. For example, if we have a short list of "

"Points, with ``__match_args__`` added, we could match it like this::"

msgstr ""

"模式可以任意地被巢套 (nested)。例如，如果我們有一個由某些點所組成的簡短 "

"list，我們就可以像這樣加入 ``__match_args__`` 來對它進行匹配： ::"

#: ../../tutorial/controlflow.rst:389

msgid ""

"class Point:\n"

" __match_args__ = ('x', 'y')\n"

" def __init__(self, x, y):\n"

" self.x = x\n"

" self.y = y\n"

"\n"

"match points:\n"

" case []:\n"

" print(\"No points\")\n"

" case [Point(0, 0)]:\n"

" print(\"The origin\")\n"

" case [Point(x, y)]:\n"

" print(f\"Single point {x}, {y}\")\n"

" case [Point(0, y1), Point(0, y2)]:\n"

" print(f\"Two on the Y axis at {y1}, {y2}\")\n"

" case _:\n"

" print(\"Something else\")"

msgstr ""

"class Point:\n"

" __match_args__ = ('x', 'y')\n"

" def __init__(self, x, y):\n"

" self.x = x\n"

" self.y = y\n"

"\n"

"match points:\n"

" case []:\n"

" print(\"No points\")\n"

" case [Point(0, 0)]:\n"

" print(\"The origin\")\n"

" case [Point(x, y)]:\n"

" print(f\"Single point {x}, {y}\")\n"

" case [Point(0, y1), Point(0, y2)]:\n"

" print(f\"Two on the Y axis at {y1}, {y2}\")\n"

" case _:\n"

" print(\"Something else\")"

#: ../../tutorial/controlflow.rst:407

msgid ""

"We can add an ``if`` clause to a pattern, known as a \"guard\". If the "

"guard is false, ``match`` goes on to try the next case block. Note that "

"value capture happens before the guard is evaluated::"

msgstr ""

"我們可以在模式中加入一個 ``if`` 子句，稱為「防護 (guard)」。如果該防護為假，"

"則 ``match`` 會繼續嘗試下一個 case 區塊。請注意，值的擷取會發生在防護的評估之"

"前： ::"

#: ../../tutorial/controlflow.rst:411

msgid ""

"match point:\n"

" case Point(x, y) if x == y:\n"

" print(f\"Y=X at {x}\")\n"

" case Point(x, y):\n"

" print(f\"Not on the diagonal\")"

msgstr ""

"match point:\n"

" case Point(x, y) if x == y:\n"

" print(f\"Y=X at {x}\")\n"

" case Point(x, y):\n"

" print(f\"Not on the diagonal\")"

#: ../../tutorial/controlflow.rst:417

msgid "Several other key features of this statement:"

msgstr "此種陳述式的其他幾個重要特色："

#: ../../tutorial/controlflow.rst:419

msgid ""

"Like unpacking assignments, tuple and list patterns have exactly the same "

"meaning and actually match arbitrary sequences. An important exception is "

"that they don't match iterators or strings."

msgstr ""

"與拆解賦值的情況類似，tuple（元組）和 list 模式具有完全相同的意義，而且實際上"

"可以匹配任意的序列。一個重要的例外，是它們不能匹配疊代器 (iterator) 或字串。"

#: ../../tutorial/controlflow.rst:423

msgid ""

"Sequence patterns support extended unpacking: ``[x, y, *rest]`` and ``(x, y, "

"*rest)`` work similar to unpacking assignments. The name after ``*`` may "

"also be ``_``, so ``(x, y, *_)`` matches a sequence of at least two items "

"without binding the remaining items."

msgstr ""

"序列模式 (sequence pattern) 可支援擴充拆解 (extended unpacking)：``[x, y, "

"*rest]`` 與 ``(x, y, *rest)`` 的作用類似於拆解賦值。``*`` 後面的名稱也可以是 "

"``_``，所以 ``(x, y, *_)`` 會匹配一個至少兩項的序列，且不會連結那兩項以外的其"

"餘項。"

#: ../../tutorial/controlflow.rst:428

msgid ""

"Mapping patterns: ``{\"bandwidth\": b, \"latency\": l}`` captures the "

"``\"bandwidth\"`` and ``\"latency\"`` values from a dictionary. Unlike "

"sequence patterns, extra keys are ignored. An unpacking like ``**rest`` is "

"also supported. (But ``**_`` would be redundant, so it is not allowed.)"

msgstr ""

"對映模式 (mapping pattern)：``{\"bandwidth\": b, \"latency\": l}`` 能從一個 "

"dictionary（字典）中擷取 ``\"bandwidth\"`` 及 ``\"latency\"`` 的值。與序列模"

"式不同，額外的鍵 (key) 會被忽略。一種像是 ``**rest`` 的拆解方式，也是可被支援"

"的。（但 ``**_`` 則是多餘的做法，所以它並不被允許。）"

#: ../../tutorial/controlflow.rst:433

msgid "Subpatterns may be captured using the ``as`` keyword::"

msgstr "使用關鍵字 ``as`` 可以擷取子模式 (subpattern)： ::"

#: ../../tutorial/controlflow.rst:435

msgid "case (Point(x1, y1), Point(x2, y2) as p2): ..."

msgstr "case (Point(x1, y1), Point(x2, y2) as p2): ..."

#: ../../tutorial/controlflow.rst:437

msgid ""

"will capture the second element of the input as ``p2`` (as long as the input "

"is a sequence of two points)"

msgstr ""

"將會擷取輸入的第二個元素作為 ``p2``\\ （只要該輸入是一個由兩個點所組成的序"

"列）。"

#: ../../tutorial/controlflow.rst:440

msgid ""

"Most literals are compared by equality, however the singletons ``True``, "

"``False`` and ``None`` are compared by identity."

msgstr ""

"大部分的字面值是藉由相等性 (equality) 來比較，但是單例物件 (singleton) "

"``True``、``False`` 和 ``None`` 是藉由標識值 (identity) 來比較。"

#: ../../tutorial/controlflow.rst:443

msgid ""

"Patterns may use named constants. These must be dotted names to prevent "

"them from being interpreted as capture variables::"

msgstr ""

"模式可以使用附名常數 (named constant)。這些模式必須是點分隔名稱，以免它們被解"

"釋為擷取變數： ::"

#: ../../tutorial/controlflow.rst:446

msgid ""

"from enum import Enum\n"

"class Color(Enum):\n"

" RED = 'red'\n"

" GREEN = 'green'\n"

" BLUE = 'blue'\n"

"\n"

"color = Color(input(\"Enter your choice of 'red', 'blue' or 'green': \"))\n"

"\n"

"match color:\n"

" case Color.RED:\n"

" print(\"I see red!\")\n"

" case Color.GREEN:\n"

" print(\"Grass is green\")\n"

" case Color.BLUE:\n"

" print(\"I'm feeling the blues :(\")"

msgstr ""

"from enum import Enum\n"

"class Color(Enum):\n"

" RED = 'red'\n"

" GREEN = 'green'\n"

" BLUE = 'blue'\n"

"\n"

"color = Color(input(\"Enter your choice of 'red', 'blue' or 'green': \"))\n"

"\n"

"match color:\n"

" case Color.RED:\n"

" print(\"I see red!\")\n"

" case Color.GREEN:\n"

" print(\"Grass is green\")\n"

" case Color.BLUE:\n"

" print(\"I'm feeling the blues :(\")"

#: ../../tutorial/controlflow.rst:462

msgid ""

"For a more detailed explanation and additional examples, you can look into :"

"pep:`636` which is written in a tutorial format."

msgstr ""

"關於更詳細的解釋和其他範例，你可以閱讀 :pep:`636`，它是以教學的格式編寫而成。"

#: ../../tutorial/controlflow.rst:468

msgid "Defining Functions"

msgstr "定義函式 (function)"

#: ../../tutorial/controlflow.rst:470

msgid ""

"We can create a function that writes the Fibonacci series to an arbitrary "

"boundary::"

msgstr "我們可以建立一個函式來產生費式數列到任何一個上界： ::"

#: ../../tutorial/controlflow.rst:473

msgid ""

">>> def fib(n): # write Fibonacci series less than n\n"

"... \"\"\"Print a Fibonacci series less than n.\"\"\"\n"

"... a, b = 0, 1\n"

"... while a < n:\n"

"... print(a, end=' ')\n"

"... a, b = b, a+b\n"

"... print()\n"

"...\n"

">>> # Now call the function we just defined:\n"