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Relative imports in Python 3
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If the __name__ is '__main__', __name__.rpartition('.')[0] returns empty string. This is why there's empty string literal in the error description:
SystemError: Parent module '' not loaded, cannot perform relative import
The relevant part of the CPython's PyImport_ImportModuleLevelObject functi...
WHERE vs HAVING
...ect_type | table | type | possible_keys | key | key_len | ref | rows | Extra |
+----+-------------+-------+-------+---------------+-------+---------+------+------+--------------------------+
| 1 | SIMPLE | table | range | value | value | 4 | NULL | 5 | U...
Can we omit parentheses when creating an object using the “new” operator?
... making a mistake you should use (new Object).func(). But I consider using extra parenthesis and extra equal signs, as in == vs ===, a bad excuse for not learning your language.
– Jean Vincent
Jun 2 '17 at 12:26
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Why is string concatenation faster than array join?
Today, I read this thread about the speed of string concatenation.
9 Answers
9
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How does collections.defaultdict work?
... as default_factory, any unknown key will return 0 by default.
Now as the string is passed in the loop, it will increase the count of those alphabets in d.
>>> s = 'mississippi'
>>> d = defaultdict(int)
>>> d.default_factory
<type 'int'>
>>> for k in s:
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Git Diff with Beyond Compare
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I don't use extra wrapper .sh files. My environment is Windows XP, git 1.7.1 on cygwin, and Beyond Compare 3. Following is my .git/config file.
[diff]
tool = bc3
[difftool]
prompt = false
[difftool "bc3"]
#use cygpath to tra...
How can I pass arguments to a batch file?
...le to redirect the output of the echo on, you need the two for-loops.
The extra characters * # are used to be safe against contents like /? (would show the help for REM).
Or a caret ^ at the line end could work as a multiline character, even in after a rem.
Then reading the rem parameter output ...
Why does an SSH remote command get fewer environment variables then when run manually? [closed]
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Having to always type extra code just to source the environment is ridiculous!
– Michael
Jan 8 '13 at 16:37
4
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How to search for a part of a word with ElasticSearch
...am of 15 over a name is probably wasteful, since very few names share a substring that long).
– rthbound
Dec 18 '13 at 23:17
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How to get current time in milliseconds in PHP?
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Use microtime. This function returns a string separated by a space. The first part is the fractional part of seconds, the second part is the integral part. Pass in true to get as a number:
var_dump(microtime()); // string(21) "0.89115400 1283846202"
var_dum...