Python 正则表达式和模式

他说，您可以使用RE查看电子邮件匹配的简单脚本

# Exercise: make a regular expression that will match an email
def test_email(your_pattern):
    pattern = re.compile(r"^(john|python-list|wha)")
    emails = ["john@example.com", "python-list@python.org", "wha.t.`1an?ug{}ly@email.com"]
    for email in emails:
        if not re.match(pattern, email):
            print "You failed to match %s" % (email)
        elif not your_pattern:
            print "Forgot to enter a pattern!"
        else:
            print "%s was found in the %s" %(str(pattern),email)
pattern = r"^(john|python-list|wha)" # Your pattern here!
test_email(pattern)

正如你在这里看到的，patter被反复提到，它既是本地的，也是全球的

variables. Eventually I've obtained results like
<_sre.SRE_Pattern object at 0x223dba0> was found in the john@example.com
<_sre.SRE_Pattern object at 0x223dba0> was found in the python-list@python.org
<_sre.SRE_Pattern object at 0x223dba0> was found in the wha.t.`1an?ug{}ly@email.

---

您需要打印匹配的组。您现在正在打印不匹配的搜索模式对象。您应该存储匹配项（如果存在），并打印它

# Exercise: make a regular expression that will match an email
def test_email(your_pattern):
    pattern = re.compile(r"^(john|python-list|wha)")
    emails = ["john@example.com", "python-list@python.org", "wha.t.`1an?ug{}ly@email.com"]
    for email in emails:
        match = re.match(pattern, email)
        if not match:
            print "You failed to match %s" % (email)
        elif not your_pattern:
            print "Forgot to enter a pattern!"
        else:
            print "%s was found in the %s" %(match.groups(), email)
pattern = r"^(john|python-list|wha)" # Your pattern here!
test_email(pattern)

还要注意，您正在覆盖函数第一行中的模式。您可能希望将其更改为：

def test_email(your_pattern):
    pattern = your_pattern # See here.
    emails = ["john@example.com", "python-list@python.org", "wha.t.`1an?ug{}ly@email.com"]
    for email in emails:
        match = re.match(pattern, email)
        if not match:
            print "You failed to match %s" % (email)
        elif not your_pattern:
            print "Forgot to enter a pattern!"
        else:
            print "%s was found in the %s" %(match.groups(), email)

请注意，

re.match

将从行首开始匹配，因此如果您需要从开始匹配，请说，

我的电子邮件是john@example.com

，您需要使用

re.search

有关

演示：

def test_email(your_pattern):
    pattern = your_pattern # See here.
    emails = ["john@example.com", "python-list@python.org", "wha.t.`1an?ug{}ly@email.com"]
    for email in emails:
        match = re.match(pattern, email)
        if not match:
            print "You failed to match %s" % (email)
        elif not your_pattern:
            print "Forgot to enter a pattern!"
        else:
            print "%s was found in the %s" %(match.groups(), email)

>>> pattern = r"^(john|python-list|wha)" # Your pattern here!
>>> test_email(pattern)
('john',) was found in the john@example.com
('python-list',) was found in the python-list@python.org
('wha',) was found in the wha.t.`1an?ug{}ly@email.com
>>>