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What is the proper way to check for null values?
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I dislike this because if you have any other type of object stuffed in the session than what you expect you may be hiding some subtle bugs in your program. I'd rather use a safe cast because I think it's likely to surface errors faster. It also a...
optional local variables in rails partial templates: how do I get out of the (defined? foo) mess?
...g syntax in my partial templates to set default values for local variables if a value wasn't explicitly defined in the :locals hash when rendering the partial --
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Bitwise operation and usage
...k on multi-bit values, but conceptually one bit at a time.
AND is 1 only if both of its inputs are 1, otherwise it's 0.
OR is 1 if one or both of its inputs are 1, otherwise it's 0.
XOR is 1 only if exactly one of its inputs are 1, otherwise it's 0.
NOT is 1 only if its input is 0, otherwise it's ...
What does [object Object] mean?
...y I'd be concerned that objects may not HAVE an id attribute; for example, if you got an object list just using a css selector like $('.someStyleClass'). To be clear on the identity of whatever object you're dealing with, it might be useful or at least interesting to assign your objects metadata usi...
MySQL Insert Where query
...as it stands will fail. Assuming your id column is unique or primary key:
If you're trying to insert a new row with ID 1 you should be using:
INSERT INTO Users(id, weight, desiredWeight) VALUES(1, 160, 145);
If you're trying to change the weight/desiredWeight values for an existing row with ID 1...
What is NODE_ENV and how to use it in Express?
...ication is run, it can check the value of the environment variable and do different things based on the value. NODE_ENV specifically is used (by convention) to state whether a particular environment is a production or a development environment. A common use-case is running additional debugging or lo...
Emulate a do-while loop in Python?
... do. You can implement a do-while loop like this:
while True:
stuff()
if fail_condition:
break
Or:
stuff()
while not fail_condition:
stuff()
What are you doing trying to use a do while loop to print the stuff in the list? Why not just use:
for i in l:
print i
print "done"
Update...
How can I run an external command asynchronously from Python?
...e Popen instance can do various other things like you can poll() it to see if it is still running, and you can communicate() with it to send it data on stdin, and wait for it to terminate.
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windows batch SET inside IF not working
...DelayedExpansion is needed.
setlocal EnableDelayedExpansion
set var1=true
if "%var1%"=="true" (
set var2=myvalue
echo !var2!
)
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How to “test” NoneType in python?
...value. So how can I question a variable that is a NoneType? I need to use if method, for example
7 Answers
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