大约有 40,000 项符合查询结果（耗时：0.0580秒） [XML]
Linux command or script counting duplicated lines in a text file?
...3
}
or you can use a simple one-liner:
$ cat filename | python3 -c 'print(__import__("json").dumps(__import__("collections").Counter(map(str.strip, __import__("fileinput").input())), indent=2))'
share
|
...
How does __proto__ differ from constructor.prototype?
...bject layout
The most surprising thing for me was discovering that Object.__proto__ points to Function.prototype, instead of Object.prototype, but I'm sure there's a good reason for that :-)
I paste the code mentioned in the image here as well for if anyone wants to test it. Note that some propert...
Format floats with standard json module
...ckage). E.g., this code:
import json
from json import encoder
encoder.FLOAT_REPR = lambda o: format(o, '.2f')
print(json.dumps(23.67))
print(json.dumps([23.67, 23.97, 23.87]))
emits:
23.67
[23.67, 23.97, 23.87]
as you desire. Obviously, there should be an architected way to override FLOAT_REP...
What is the effect of extern “C” in C++?
...n it posted yet.
You'll very often see code in C headers like so:
#ifdef __cplusplus
extern "C" {
#endif
// all of your legacy C code here
#ifdef __cplusplus
}
#endif
What this accomplishes is that it allows you to use that C header file with your C++ code, because the macro "__cplusplus" will...
Cross-Origin Request Headers(CORS) with PHP headers
...nitty-gritty low-down, read:
*
* - https://developer.mozilla.org/en/HTTP_access_control
* - http://www.w3.org/TR/cors/
*
*/
function cors() {
// Allow from any origin
if (isset($_SERVER['HTTP_ORIGIN'])) {
// Decide if the origin in $_SERVER['HTTP_ORIGIN'] is one
// yo...
Printing without newline (print 'a',) prints a space, how to remove?
... you to set an end parameter. You can use it in >=2.6 by importing from __future__. I'd avoid this in any serious 2.x code though, as it will be a little confusing for those who have never used 3.x. However, it should give you a taste of some of the goodness 3.x brings.
>>> from __futur...
Multiple commands in gdb separated by some sort of delimiter ';'?
...with a function to run multiple commands.
# multiple commands
python
from __future__ import print_function
import gdb
class Cmds(gdb.Command):
"""run multiple commands separated by ';'"""
def __init__(self):
gdb.Command.__init__(
self,
"cmds",
gdb.COMMAND_DATA,
gdb...
How to import module when module name has a '-' dash or hyphen in it?
...
you can't. foo-bar is not an identifier. rename the file to foo_bar.py
Edit: If import is not your goal (as in: you don't care what happens with sys.modules, you don't need it to import itself), just getting all of the file's globals into your own scope, you can use execfile
# contents...
Adding information to an exception?
....message +
' happens at %s' % arg1), sys.exc_info()[2]
bar('arg1')
Traceback (most recent call last):
File "test.py", line 16, in <module>
bar('arg1')
File "test.py", line 11, in bar
foo()
File "test.py", line 5, in foo
raise IOError('Stuff...
Forced naming of parameters in Python
...ition to other good answers for Python 2, please consider the following:
__named_only_start = object()
def info(param1,param2,param3,_p=__named_only_start,spacing=10,collapse=1):
if _p is not __named_only_start:
raise TypeError("info() takes at most 3 positional arguments")
return...