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valueOf() vs. toString() in Javascript
...operands, and then decides if addition or concatenation should be applied, based on the type of each primitive.
So, this is how you think it works
a + b:
pa = ToPrimitive(a)
if(pa is string)
return concat(pa, ToString(b))
else
return add(pa, ToNumber(b))
and this is wha...
How to upgrade rubygems
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you command doesn't work on distribution based on debian gem update --system "2.1.0" ERROR: While executing gem ... (RuntimeError) gem update --system is disabled on Debian, because it will overwrite the content of the rubygems Debian package, and might break your D...
What does “coalgebra” mean in the context of programming?
...rmation Identity → f.
Now we can think about a monad as just an algebra based around some functor f with operations f ∘ f → f and Identity → f. Doesn't this look familiar? It's very similar to a monoid, which was just some type τ with operations τ × τ → τ and () → τ.
So a monad i...
Freeing up a TCP/IP port?
...ou :-).
What are you actually trying to achieve here? Solutions will vary based on the processes holding those ports.
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Objective-C formatting string for boolean?
... evaluates the boxed expression and returns the appropriate object literal based on its value (i.e. NSString for const char*, NSNumber for int, etc.).
Sqlite or MySql? How to decide? [closed]
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Their feature sets are not at all the same. Sqlite is an embedded database which has no network capabilities (unless you add them). So you can't use it on a network.
If you need
Network access - for example accessing from another machine;
Any real degree of concurrency - for example, if you...
What is the purpose of the -m switch?
...ause its package will be loaded along the way. 3) Absolute imports will be based on your current directory, not the directory where the .py file is ('' is at the head of sys.path, rather than /path/to/my, if the script is at /path/to/my/script.py).
– clacke
Sep...
Python Remove last 3 characters of a string
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It doesn't work as you expect because strip is character based. You need to do this instead:
foo = foo.replace(' ', '')[:-3].upper()
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Days between two dates? [duplicate]
...ents on other answers. This is how I would work out the difference in days based on 24 hours and calender days. the days attribute works well for 24 hours and the function works best for calendar checks.
from datetime import timedelta, datetime
def cal_days_diff(a,b):
A = a.replace(hour = 0, ...
Git for beginners: The definitive practical guide
... using git to track that project). Simply remove the .git directory at the base level of the repository.
cd ~/code/project001/
rm -rf .git/
Caution: This will destroy all revision history, all your tags, everything git has done. It will not touch the "current" files (the files you can currently see...