March 2018
Beginner to intermediate
624 pages
16h 10m
Japanese
Content preview from Head First Python 第2版 ―頭とからだで覚えるPythonの基本
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関数内の関数
関数に関数を渡す。
関数から関数を返す。
任意の数のあらゆる型
の引数を処理。
引数のリストを受け取る
いくつでも引数を指定できる関数（この例では
myfunc
と呼びます）を作成する場合を
想像してください。例えば、
myfunc
を次のように呼び出すこともあれば、
myfunc(10)
次のように呼び出すこともあり、
myfunc()
または、次のように呼び出すこともあります。
myfunc(10, 20, 30, 40, 50, 60, 70)
実際には、
myfunc
は任意の数の引数で呼び出されるのですが、数は事前にはわかりま
せん。
3
つの異なるバージョンの
myfunc
を定義して上の
3
つの呼び出しを処理することはで
きないので、「関数で任意の数の引数を取ることは可能なのか」という疑問が生じます。
*
を使って可変長の引数リストを受け取る
Python
には、関数が任意の数の引数を取れることを示す特殊な表記があります（「任意
の数」とは「ゼロ個以上」という意味で
す）。この表記では
*
を使って任意の数を表し、引数
名（慣例により
args
を使います）と組み合わせて関数が可変長の引数リストを取れるこ
とを示します（ただし、
*args
は厳密にはタプルです）。
下は、この表記を使って呼び出し時に任意の数の引数を取るようにした
myfunc
です。
引数を指定すると、
myfunc
はその値を画面に表示します。
390
10
章
もう少しです。あと
1
つでデコレータを
作成する準備が整います。
引数
1
つ
引数なし
いくつもの引数
（この例ではすべて数値 ...
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O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.