{"id":822,"date":"2012-07-31T22:17:40","date_gmt":"2012-07-31T14:17:40","guid":{"rendered":"http:\/\/notes.zerobox.org\/?p=822"},"modified":"2012-07-31T22:17:40","modified_gmt":"2012-07-31T14:17:40","slug":"17%e4%b8%aa%e6%96%b0%e6%89%8b%e5%b8%b8%e8%a7%81python%e8%bf%90%e8%a1%8c%e6%97%b6%e9%94%99%e8%af%af","status":"publish","type":"post","link":"http:\/\/zerobox.org\/notes\/822.html","title":{"rendered":"17\u4e2a\u65b0\u624b\u5e38\u89c1Python\u8fd0\u884c\u65f6\u9519\u8bef"},"content":{"rendered":"

\u5f53\u521d\u5b66 Python \u65f6\uff0c\u60f3\u8981\u5f04\u61c2 Python \u7684\u9519\u8bef\u4fe1\u606f\u7684\u542b\u4e49\u53ef\u80fd\u6709\u70b9\u590d\u6742\u3002\u8fd9\u91cc\u5217\u51fa\u4e86\u5e38\u89c1\u7684\u7684\u4e00\u4e9b\u8ba9\u4f60\u7a0b\u5e8f crash \u7684\u8fd0\u884c\u65f6\u9519\u8bef\u3002<\/p>\n

1\uff09\u5fd8\u8bb0\u5728 if , elif , else , for , while , class ,def \u58f0\u660e\u672b\u5c3e\u6dfb\u52a0 \uff1a\uff08\u5bfc\u81f4 \u201cSyntaxError \uff1ainvalid syntax\u201d\uff09<\/strong><\/p>\n

\u8be5\u9519\u8bef\u5c06\u53d1\u751f\u5728\u7c7b\u4f3c\u5982\u4e0b\u4ee3\u7801\u4e2d\uff1a<\/p>\n

\n
if\u00a0spam\u00a0==\u00a042<\/li>\n
\u00a0\u00a0\u00a0\u00a0print(‘Hello!’)<\/li>\n<\/ol>\n
2)\u4f7f\u7528 = \u800c\u4e0d\u662f ==\uff08\u5bfc\u81f4\u201cSyntaxError: invalid syntax\u201d\uff09<\/strong><\/p>\n
= \u662f\u8d4b\u503c\u64cd\u4f5c\u7b26\u800c == \u662f\u7b49\u4e8e\u6bd4\u8f83\u64cd\u4f5c\u3002\u8be5\u9519\u8bef\u53d1\u751f\u5728\u5982\u4e0b\u4ee3\u7801\u4e2d\uff1a<\/p>\n
\n
if\u00a0spam\u00a0=\u00a042:<\/li>\n
\u00a0\u00a0\u00a0\u00a0print(‘Hello!’)<\/li>\n<\/ol>\n
3\uff09\u9519\u8bef\u7684\u4f7f\u7528\u7f29\u8fdb\u91cf\u3002\uff08\u5bfc\u81f4\u201cIndentationError\uff1aunexpected indent\u201d\u3001\u201cIndentationError\uff1aunindent does not match any outer indetation level\u201d\u4ee5\u53ca\u201cIndentationError\uff1aexpected an indented block\u201d\uff09<\/strong><\/p>\n
\u8bb0\u4f4f\u7f29\u8fdb\u589e\u52a0\u53ea\u7528\u5728\u4ee5\uff1a\u7ed3\u675f\u7684\u8bed\u53e5\u4e4b\u540e\uff0c\u800c\u4e4b\u540e\u5fc5\u987b\u6062\u590d\u5230\u4e4b\u524d\u7684\u7f29\u8fdb\u683c\u5f0f\u3002\u8be5\u9519\u8bef\u53d1\u751f\u5728\u5982\u4e0b\u4ee3\u7801\u4e2d\uff1a<\/p>\n
\n
print(‘Hello!’)<\/li>\n
\u00a0\u00a0\u00a0\u00a0print(‘Howdy!’)<\/li>\n
\u6216\u8005\uff1a<\/li>\n
if\u00a0spam\u00a0==\u00a042:<\/li>\n
\u00a0\u00a0\u00a0\u00a0print(‘Hello!’)<\/li>\n
\u00a0\u00a0print(‘Howdy!’)<\/li>\n
\u6216\u8005\uff1a<\/li>\n
if\u00a0spam\u00a0==\u00a042:<\/li>\n
print(‘Hello!’)<\/li>\n<\/ol>\n
4\uff09\u5728 for \u5faa\u73af\u8bed\u53e5\u4e2d\u5fd8\u8bb0\u8c03\u7528 len() (\u5bfc\u81f4\u201cTypeError: ‘list’ object cannot be interpreted as an integer\u201d)<\/strong><\/p>\n
\u901a\u5e38\u4f60\u60f3\u8981\u901a\u8fc7\u7d22\u5f15\u6765\u8fed\u4ee3\u4e00\u4e2alist\u6216\u8005string\u7684\u5143\u7d20\uff0c\u8fd9\u9700\u8981\u8c03\u7528 range() \u51fd\u6570\u3002\u8981\u8bb0\u5f97\u8fd4\u56delen \u503c\u800c\u4e0d\u662f\u8fd4\u56de\u8fd9\u4e2a\u5217\u8868\u3002<\/p>\n
\u8be5\u9519\u8bef\u53d1\u751f\u5728\u5982\u4e0b\u4ee3\u7801\u4e2d\uff1a<\/p>\n
\n
spam\u00a0=\u00a0[‘cat’,\u00a0‘dog’,\u00a0‘mouse’]<\/li>\n
for\u00a0i\u00a0in\u00a0range(spam):<\/li>\n
\u00a0\u00a0\u00a0\u00a0print(spam[i])<\/li>\n<\/ol>\n
5\uff09\u5c1d\u8bd5\u4fee\u6539string\u7684\u503c\uff08\u5bfc\u81f4\u201cTypeError: ‘str’ object does not support item assignment\u201d\uff09<\/strong><\/p>\n
string\u662f\u4e00\u79cd\u4e0d\u53ef\u53d8\u7684\u6570\u636e\u7c7b\u578b\uff0c\u8be5\u9519\u8bef\u53d1\u751f\u5728\u5982\u4e0b\u4ee3\u7801\u4e2d\uff1a<\/p>\n
\n
spam\u00a0=\u00a0‘I\u00a0have\u00a0a\u00a0pet\u00a0cat.’<\/li>\n
spam[13]\u00a0=\u00a0‘r’<\/li>\n
print(spam)<\/li>\n<\/ol>\n
\u800c\u4f60\u5b9e\u9645\u60f3\u8981\u8fd9\u6837\u505a\uff1a<\/p>\n
\n
spam\u00a0=\u00a0‘I\u00a0have\u00a0a\u00a0pet\u00a0cat.’<\/li>\n
spam\u00a0=\u00a0spam[:13]\u00a0+\u00a0‘r’\u00a0+\u00a0spam[14:]<\/li>\n
print(spam)<\/li>\n<\/ol>\n
6\uff09\u5c1d\u8bd5\u8fde\u63a5\u975e\u5b57\u7b26\u4e32\u503c\u4e0e\u5b57\u7b26\u4e32\uff08\u5bfc\u81f4 \u201cTypeError: Can’t convert ‘int’ object to str implicitly\u201d\uff09<\/strong><\/p>\n
\u8be5\u9519\u8bef\u53d1\u751f\u5728\u5982\u4e0b\u4ee3\u7801\u4e2d\uff1a<\/p>\n
\n
numEggs\u00a0=\u00a012<\/li>\n
print(‘I\u00a0have\u00a0‘\u00a0+\u00a0numEggs\u00a0+\u00a0‘\u00a0eggs.’)<\/li>\n<\/ol>\n
\u800c\u4f60\u5b9e\u9645\u60f3\u8981\u8fd9\u6837\u505a\uff1a<\/p>\n
\n
numEggs\u00a0=\u00a012<\/li>\n
print(‘I\u00a0have\u00a0‘\u00a0+\u00a0str(numEggs)\u00a0+\u00a0‘\u00a0eggs.’)<\/li>\n
\u6216\u8005\uff1a<\/li>\n
numEggs\u00a0=\u00a012<\/li>\n
print(‘I\u00a0have\u00a0%s\u00a0eggs.’\u00a0%\u00a0(numEggs))<\/li>\n<\/ol>\n
7\uff09\u5728\u5b57\u7b26\u4e32\u9996\u5c3e\u5fd8\u8bb0\u52a0\u5f15\u53f7\uff08\u5bfc\u81f4\u201cSyntaxError: EOL while scanning string literal\u201d\uff09<\/strong><\/p>\n
\u8be5\u9519\u8bef\u53d1\u751f\u5728\u5982\u4e0b\u4ee3\u7801\u4e2d\uff1a<\/p>\n
\n
print(Hello!’)<\/li>\n
\u6216\u8005:<\/li>\n
print(‘Hello!)<\/li>\n
\u6216\u8005:<\/li>\n
myName\u00a0=\u00a0‘Al’<\/li>\n
print(‘My\u00a0name\u00a0is\u00a0‘\u00a0+\u00a0myName\u00a0+\u00a0.\u00a0How\u00a0are\u00a0you?’)<\/li>\n<\/ol>\n
8\uff09\u53d8\u91cf\u6216\u8005\u51fd\u6570\u540d\u62fc\u5199\u9519\u8bef\uff08\u5bfc\u81f4\u201cNameError: name ‘fooba’ is not defined\u201d\uff09<\/strong><\/p>\n
\n
foobar\u00a0=\u00a0‘Al’<\/li>\n
print(‘My\u00a0name\u00a0is\u00a0‘\u00a0+\u00a0fooba)<\/li>\n
\u6216\u8005:<\/li>\n
spam\u00a0=\u00a0ruond(4.2)<\/li>\n
\u6216\u8005:<\/li>\n
spam\u00a0=\u00a0Round(4.2)<\/li>\n<\/ol>\n
9\uff09\u65b9\u6cd5\u540d\u62fc\u5199\u9519\u8bef\uff08\u5bfc\u81f4 \u201cAttributeError: ‘str’ object has no attribute ‘lowerr’\u201d\uff09<\/strong><\/p>\n
\n
spam\u00a0=\u00a0‘THIS\u00a0IS\u00a0IN\u00a0LOWERCASE.’<\/li>\n
spam\u00a0=\u00a0spam.lowerr()<\/li>\n<\/ol>\n
10\uff09\u5f15\u7528\u8d85\u8fc7list\u6700\u5927\u7d22\u5f15\uff08\u5bfc\u81f4\u201cIndexError: list index out of range\u201d\uff09<\/strong><\/p>\n
\u8be5\u9519\u8bef\u53d1\u751f\u5728\u5982\u4e0b\u4ee3\u7801\u4e2d\uff1a<\/p>\n
\n
spam\u00a0=\u00a0[‘cat’,\u00a0‘dog’,\u00a0‘mouse’]<\/li>\n
print(spam[6])<\/li>\n<\/ol>\n
<\/p>\n
11\uff09\u4f7f\u7528\u4e0d\u5b58\u5728\u7684\u5b57\u5178\u952e\u503c\uff08\u5bfc\u81f4\u201cKeyError\uff1a\u2018spam\u2019\u201d\uff09<\/strong><\/p>\n
\u8be5\u9519\u8bef\u53d1\u751f\u5728\u5982\u4e0b\u4ee3\u7801\u4e2d\uff1a<\/p>\n
\n
spam\u00a0=\u00a0{‘cat’:\u00a0‘Zophie’,\u00a0‘dog’:\u00a0‘Basil’,\u00a0‘mouse’:\u00a0‘Whiskers’}<\/li>\n
print(‘The\u00a0name\u00a0of\u00a0my\u00a0pet\u00a0zebra\u00a0is\u00a0‘\u00a0+\u00a0spam[‘zebra’])<\/li>\n<\/ol>\n
12\uff09\u5c1d\u8bd5\u4f7f\u7528Python\u5173\u952e\u5b57\u4f5c\u4e3a\u53d8\u91cf\u540d\uff08\u5bfc\u81f4\u201cSyntaxError\uff1ainvalid syntax\u201d\uff09<\/strong><\/p>\n
Python\u5173\u952e\u4e0d\u80fd\u7528\u4f5c\u53d8\u91cf\u540d\uff0c\u8be5\u9519\u8bef\u53d1\u751f\u5728\u5982\u4e0b\u4ee3\u7801\u4e2d\uff1a<\/p>\n
\n
class\u00a0=\u00a0‘algebra’<\/li>\n<\/ol>\n
Python3\u7684\u5173\u952e\u5b57\u6709\uff1aand, as, assert, break, class, continue, def, del, elif, else, except, False, finally, for, from, global, if, import, in, is, lambda, None, nonlocal, not, or, pass, raise, return, True, try, while, with, yield<\/p>\n
13\uff09\u5728\u4e00\u4e2a\u5b9a\u4e49\u65b0\u53d8\u91cf\u4e2d\u4f7f\u7528\u589e\u503c\u64cd\u4f5c\u7b26\uff08\u5bfc\u81f4\u201cNameError: name ‘foobar’ is not defined\u201d\uff09<\/strong><\/p>\n
\u4e0d\u8981\u5728\u58f0\u660e\u53d8\u91cf\u65f6\u4f7f\u75280\u6216\u8005\u7a7a\u5b57\u7b26\u4e32\u4f5c\u4e3a\u521d\u59cb\u503c\uff0c\u8fd9\u6837\u4f7f\u7528\u81ea\u589e\u64cd\u4f5c\u7b26\u7684\u4e00\u53e5spam += 1\u7b49\u4e8espam = spam + 1\uff0c\u8fd9\u610f\u5473\u7740spam\u9700\u8981\u6307\u5b9a\u4e00\u4e2a\u6709\u6548\u7684\u521d\u59cb\u503c\u3002<\/p>\n
\u8be5\u9519\u8bef\u53d1\u751f\u5728\u5982\u4e0b\u4ee3\u7801\u4e2d\uff1a<\/p>\n
\n
spam\u00a0=\u00a00<\/li>\n
spam\u00a0+=\u00a042<\/li>\n
eggs\u00a0+=\u00a042<\/li>\n<\/ol>\n
14\uff09\u5728\u5b9a\u4e49\u5c40\u90e8\u53d8\u91cf\u524d\u5728\u51fd\u6570\u4e2d\u4f7f\u7528\u5c40\u90e8\u53d8\u91cf\uff08\u6b64\u65f6\u6709\u4e0e\u5c40\u90e8\u53d8\u91cf\u540c\u540d\u7684\u5168\u5c40\u53d8\u91cf\u5b58\u5728\uff09\uff08\u5bfc\u81f4\u201cUnboundLocalError: local variable ‘foobar’ referenced before assignment\u201d\uff09<\/strong><\/p>\n
\u5728\u51fd\u6570\u4e2d\u4f7f\u7528\u5c40\u90e8\u53d8\u6765\u90a3\u4e2a\u800c\u540c\u65f6\u53c8\u5b58\u5728\u540c\u540d\u5168\u5c40\u53d8\u91cf\u65f6\u662f\u5f88\u590d\u6742\u7684\uff0c\u4f7f\u7528\u89c4\u5219\u662f\uff1a\u5982\u679c\u5728\u51fd\u6570\u4e2d\u5b9a\u4e49\u4e86\u4efb\u4f55\u4e1c\u897f\uff0c\u5982\u679c\u5b83\u53ea\u662f\u5728\u51fd\u6570\u4e2d\u4f7f\u7528\u90a3\u5b83\u5c31\u662f\u5c40\u90e8\u7684\uff0c\u53cd\u4e4b\u5c31\u662f\u5168\u5c40\u53d8\u91cf\u3002<\/p>\n
\u8fd9\u610f\u5473\u7740\u4f60\u4e0d\u80fd\u5728\u5b9a\u4e49\u5b83\u4e4b\u524d\u628a\u5b83\u5f53\u5168\u5c40\u53d8\u91cf\u5728\u51fd\u6570\u4e2d\u4f7f\u7528\u3002<\/p>\n
\u8be5\u9519\u8bef\u53d1\u751f\u5728\u5982\u4e0b\u4ee3\u7801\u4e2d\uff1a<\/p>\n
\n
someVar\u00a0=\u00a042<\/li>\n
def\u00a0myFunction():<\/li>\n
\u00a0\u00a0\u00a0\u00a0print(someVar)<\/li>\n
\u00a0\u00a0\u00a0\u00a0someVar\u00a0=\u00a0100<\/li>\n
myFunction()<\/li>\n<\/ol>\n
15\uff09\u5c1d\u8bd5\u4f7f\u7528 range()\u521b\u5efa\u6574\u6570\u5217\u8868\uff08\u5bfc\u81f4\u201cTypeError: ‘range’ object does not support item assignment\u201d\uff09<\/strong><\/p>\n
\u6709\u65f6\u4f60\u60f3\u8981\u5f97\u5230\u4e00\u4e2a\u6709\u5e8f\u7684\u6574\u6570\u5217\u8868\uff0c\u6240\u4ee5 range() \u770b\u4e0a\u53bb\u662f\u751f\u6210\u6b64\u5217\u8868\u7684\u4e0d\u9519\u65b9\u5f0f\u3002\u7136\u800c\uff0c\u4f60\u9700\u8981\u8bb0\u4f4f range() \u8fd4\u56de\u7684\u662f \u201crange object\u201d\uff0c\u800c\u4e0d\u662f\u5b9e\u9645\u7684 list \u503c\u3002<\/p>\n
\u8be5\u9519\u8bef\u53d1\u751f\u5728\u5982\u4e0b\u4ee3\u7801\u4e2d\uff1a<\/p>\n
\n
spam\u00a0=\u00a0range(10)<\/li>\n
spam[4]\u00a0=\u00a0-1<\/li>\n<\/ol>\n
\u4e5f\u8bb8\u8fd9\u624d\u662f\u4f60\u60f3\u505a\uff1a<\/p>\n
\n
spam\u00a0=\u00a0list(range(10))<\/li>\n
spam[4]\u00a0=\u00a0-1<\/li>\n<\/ol>\n
\uff08\u6ce8\u610f\uff1a\u5728 Python 2 \u4e2d spam = range(10) \u662f\u80fd\u884c\u7684\uff0c\u56e0\u4e3a\u5728 Python 2 \u4e2d range() \u8fd4\u56de\u7684\u662flist\u503c\uff0c\u4f46\u662f\u5728 Python 3 \u4e2d\u5c31\u4f1a\u4ea7\u751f\u4ee5\u4e0a\u9519\u8bef\uff09<\/p>\n
16\uff09\u4e0d\u9519\u5728 ++ \u6216\u8005 — \u81ea\u589e\u81ea\u51cf\u64cd\u4f5c\u7b26\u3002\uff08\u5bfc\u81f4\u201cSyntaxError: invalid syntax\u201d\uff09<\/p>\n
\u5982\u679c\u4f60\u4e60\u60ef\u4e8e\u4f8b\u5982 C++ , Java , PHP \u7b49\u5176\u4ed6\u7684\u8bed\u8a00\uff0c\u4e5f\u8bb8\u4f60\u4f1a\u60f3\u8981\u5c1d\u8bd5\u4f7f\u7528 ++ \u6216\u8005 — \u81ea\u589e\u81ea\u51cf\u4e00\u4e2a\u53d8\u91cf\u3002\u5728Python\u4e2d\u662f\u6ca1\u6709\u8fd9\u6837\u7684\u64cd\u4f5c\u7b26\u7684\u3002<\/p>\n
\u8be5\u9519\u8bef\u53d1\u751f\u5728\u5982\u4e0b\u4ee3\u7801\u4e2d\uff1a<\/p>\n
\n
spam\u00a0=\u00a01<\/li>\n
spam++<\/li>\n<\/ol>\n
\u4e5f\u8bb8\u8fd9\u624d\u662f\u4f60\u60f3\u505a\u7684\uff1a<\/p>\n
\n
spam\u00a0=\u00a01<\/li>\n
spam\u00a0+=\u00a01<\/li>\n<\/ol>\n
17\uff09\u5fd8\u8bb0\u4e3a\u65b9\u6cd5\u7684\u7b2c\u4e00\u4e2a\u53c2\u6570\u6dfb\u52a0self\u53c2\u6570\uff08\u5bfc\u81f4\u201cTypeError: myMethod() takes no arguments (1 given)\u201d\uff09<\/p>\n
\u8be5\u9519\u8bef\u53d1\u751f\u5728\u5982\u4e0b\u4ee3\u7801\u4e2d\uff1a<\/p>\n
\n
class\u00a0Foo():<\/li>\n
\u00a0\u00a0\u00a0\u00a0def\u00a0myMethod():<\/li>\n
\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0\u00a0print(‘Hello!’)<\/li>\n
a\u00a0=\u00a0Foo()<\/li>\n
a.myMethod()<\/li>\n<\/ol>\n
\u539f\u6587\u94fe\u63a5\uff1ahttp:\/\/www.oschina.net\/question\/89964_62779<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"
\u5f53\u521d\u5b66 Python \u65f6\uff0c\u60f3\u8981\u5f04\u61c2 Python \u7684\u9519\u8bef\u4fe1\u606f\u7684\u542b\u4e49\u53ef\u80fd\u6709\u70b9\u590d\u6742\u3002 …<\/p>\n
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