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Using boolean values in C
...e 1
#define false 0
Explanation
Option 1 will work only if you use C99 and it's the "standard way" to do it. Choose this if possible.
Options 2, 3 and 4 will have in practice the same identical behavior. #2 and #3 don't use #defines though, which in my opinion is better.
If you are undecided, ...
No Multiline Lambda in Python: Why not?
...r syntax constructs in Python. I was thinking about this on the bus today and realized I couldn't think of a single Python construct that multiline lambdas clash with. Given that I know the language pretty well, this surprised me.
...
Abort makefile if variable not set
...ning an auxiliary function for that:
# Check that given variables are set and all have non-empty values,
# die with an error otherwise.
#
# Params:
# 1. Variable name(s) to test.
# 2. (optional) Error message to print.
check_defined = \
$(strip $(foreach 1,$1, \
$(call __check_defin...
What is the meaning of “$” sign in JavaScript
...from one of the popular JavaScript libraries (jQuery, ProtoType, mooTools, and so on).
There's nothing mysterious about the use of $ in JavaScript. $ is simply a valid JavaScript identifier.
JavaScript allows upper and lower letters, numbers, and $ and _. The $ was intended to be used for machine-...
Can I assume (bool)true == (int)1 for any C++ compiler?
...are redundant. In your expression:
true == 1
Integral promotion applies and the bool value will be promoted to an int and this promotion must yield 1.
Reference: 4.7 [conv.integral] / 4: If the source type is bool... true is converted to one.
...
What is causing this ActiveRecord::ReadOnlyRecord error?
...
Rails 2.3.3 and lower
From the ActiveRecord CHANGELOG(v1.12.0, October 16th, 2005):
Introduce read-only records. If you call object.readonly! then it will
mark the object as read-only and raise
ReadOnlyRecord if you call
obje...
How to change identity column values programmatically?
...
You need to
set identity_insert YourTable ON
Then delete your row and reinsert it with different identity.
Once you have done the insert don't forget to turn identity_insert off
set identity_insert YourTable OFF
...
Is it possible to read from a InputStream with a timeout?
...tream always returns 0.
This method should be overridden by subclasses.
And indeed, the concrete input stream classes do override available(), providing meaningful values, not constant 0s.
Second Caveat: Ensure you use carriage-return when typing input in Windows.
If using System.in, your progr...
How can I sort generic list DESC and ASC?
How can I sort generic list DESC and ASC? With LINQ and without LINQ? I'm using VS2008.
5 Answers
...
Animated loading image in picasso
...gh is an animated spinning progress bar style spinner that animates around and around while the image is loading, like I see in most professional apps. Picasso doesn't seem to support this, only static image drawables. Is there a way to get it working with Picasso or do I have to do something differ...