大约有 40,000 项符合查询结果（耗时：0.0595秒） [XML]
Should I use a class or dictionary?
...vantage? What happens if you later want to add some code? Where would your __init__ code go?
Classes are for bundling related data (and usually code).
Dictionaries are for storing key-value relationships, where usually the keys are all of the same type, and all the values are also of one type. Occ...
Error on renaming database in SQL Server 2008 R2
...
32
In SQL Server Management Studio (SSMS):
You can also right click your database in the Object E...
How to implement Enums in Ruby?
...
325
Two ways. Symbols (:foo notation) or constants (FOO notation).
Symbols are appropriate when y...
Python division
...t:
>>> float(10 - 20) / (100 - 10)
-0.1111111111111111
or from __future__ import division, which the forces / to adopt Python 3.x's behavior that always returns a float.
>>> from __future__ import division
>>> (10 - 20) / (100 - 10)
-0.1111111111111111
...
Rails update_attributes without save?
...nswered Aug 2 '12 at 17:54
Ajedi32Ajedi32
33.7k1717 gold badges110110 silver badges151151 bronze badges
...
Why 0 is true but false is 1 in the shell?
...
Zero is encoding-independent.
If we wanted to store one(1) in a 32-bit integer word, the first question would be "big-endian word or little-endian word?", followed by "how long are the bytes composing a little-endian word?", while zero will always look the same.
Also it needs to be e...
What is scope/named_scope in rails?
...000/svg\"\u003e\u003cpath d=\"M46.1709 9.17788C46.1709 8.26454 46.2665 7.94324 47.1084 7.58816C47.4091 7.46349 47.7169 7.36433 48.0099 7.26993C48.9099 6.97997 49.672 6.73443 49.672 5.93063C49.672 5.22043 48.9832 4.61182 48.1414 4.61182C47.4335 4.61182 46.7256 4.91628 46.0943 5.50789C45.7307 4.9328 4...
Order discrete x scale by frequency/value
...
eflores89eflores89
23788 silver badges2323 bronze badges
...
Why is whitespace sometimes needed around metacharacters?
...
Charles Duffy
218k3232 gold badges273273 silver badges333333 bronze badges
answered Jan 17 '14 at 13:09
Peter WestlakeP...
How can I propagate exceptions between threads?
We have a function which a single thread calls into (we name this the main thread). Within the body of the function we spawn multiple worker threads to do CPU intensive work, wait for all threads to finish, then return the result on the main thread.
...