python编程教程交互式联系_Python Koans交互式教程
Python Koans是一个学习Python编程语言的交互式教程，通过解决当中的问题来更深刻地理解Python。本系列文章为在此项目的学习中的问题解决方案及思考
Lesson 2 String
字符串是 Python 中最常用的数据类型。我们可以使用引号’或”来创建字符串。
about_strings.py
#!/usr/bin/env python
# -*- coding: utf-8 -*-
from runner.koan import *
class AboutStrings(Koan):
def test_double_quoted_strings_are_strings(self):
string = "Hello, world."
self.assertEqual(True, isinstance(string, str))
def test_single_quoted_strings_are_also_strings(self):
string = 'Goodbye, world.'
self.assertEqual(True, isinstance(string, str))
def test_triple_quote_strings_are_also_strings(self):
string = """Howdy, world!"""
self.assertEqual(True, isinstance(string, str))
def test_triple_single_quotes_work_too(self):
string = '''Bonjour tout le monde!'''
self.assertEqual(True, isinstance(string, str))
def test_raw_strings_are_also_strings(self):
string = r"Konnichi wa, world!"
self.assertEqual(True, isinstance(string, str))
def test_use_single_quotes_to_create_string_with_double_quotes(self):
string = 'He said, "Go Away."'
self.assertEqual('He said, "Go Away."', string)
def test_use_double_quotes_to_create_strings_with_single_quotes(self):
string = "Don't"
self.assertEqual("Don't", string)
def test_use_backslash_for_escaping_quotes_in_strings(self):
a = "He said, "Don't""
b = 'He said, "Don't"'
self.assertEqual(True, (a == b))
def test_use_backslash_at_the_end_of_a_line_to_continue_onto_the_next_line(self):
string = "It was the best of times,n
It was the worst of times."
self.assertEqual(52, len(string))
def test_triple_quoted_strings_can_span_lines(self):
string = """
Howdy,
world!
"""
self.assertEqual(15, len(string))
def test_triple_quoted_strings_need_less_escaping(self):
a = "Hello "world"."
b = """Hello "world"."""
self.assertEqual(True, (a == b))
def test_escaping_quotes_at_the_end_of_triple_quoted_string(self):
string = """Hello "world""""
self.assertEqual("""Hello "world"""", string)
def test_plus_concatenates_strings(self):
string = "Hello, " + "world"
self.assertEqual("Hello, world", string)
def test_adjacent_strings_are_concatenated_automatically(self):
string = "Hello" ", " "world"
self.assertEqual("Hello, world", string)
def test_plus_will_not_modify_original_strings(self):
hi = "Hello, "
there = "world"
string = hi + there
self.assertEqual("Hello, ", hi)
self.assertEqual("world", there)
def test_plus_equals_will_append_to_end_of_string(self):
hi = "Hello, "
there = "world"
hi += there
self.assertEqual("Hello, world", hi)
def test_plus_equals_also_leaves_original_string_unmodified(self):
original = "Hello, "
hi = original
there = "world"
hi += there
self.assertEqual("Hello, ", original)
def test_most_strings_interpret_escape_characters(self):
string = "n"
self.assertEqual('n', string)
self.assertEqual("""n""", string)
self.assertEqual(1, len(string))