Python3の色々

tips
version8

1. はじめに

Pythonの書き方を毎度忘れるので忘れがちなことをメモしておく

2. 宣言色々

初期化

3. リスト内包表記

書き方

cmp_list = [i for i in range(10)]
# [0,1,2,3,4,5,6,7,8,9]
cmp_set  = {i for i in range(10)}
# {0,1,2,3,4,5,6,7,8,9}
cmp_dict = {i:i for i in range(10)}
# {0:0,1:1,2:2,3:3,4:4,5:5,6:6,7:7,8:8,9:9}

関連事項

ext_list []
for i in range(10):
    ext_list.append(i)

4. assert

起きないパターン

assert "aaa" , "hogehoge"
assert True  , "hogehoge"
assert ["aa"],"hoge"
assert [""]  ,"hoge"
assert 1     ,"hoge"
assert -1    ,"hoge"

起きるパターン

assert False, "hogehoge"
#Traceback (most recent call last):
# File "<stdin>", line 1, in <module>
# AssertionError: hogehoge
assert ""   , "hogehoge"
# Traceback (most recent call last):
#   File "<stdin>", line 1, in <module>
# AssertionError: hogehoge
assert None , "hogehoge"
# Traceback (most recent call last):
#   File "<stdin>", line 1, in <module>
# AssertionError: hogehoge
assert []   ,"hoge"
# Traceback (most recent call last):
#   File "<stdin>", line 1, in <module>
# AssertionError: hogehoge
assert 0    ,"hoge"
# Traceback (most recent call last):
#   File "<stdin>", line 1, in <module>
# AssertionError: hogehoge

参考