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What is the difference between string primitives and String objects in JavaScript?
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JavaScript has two main type categories, primivites and objects.
var s = 'test';
var ss = new String('test');
The single quote/double quote patterns are identical in terms of functionality. That aside, the behaviour you are trying to name is called auto-boxing. So what actu...
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.
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How do I conditionally apply CSS styles in AngularJS?
...ange dynamically. Think programmable control of the style values.
ng-show and ng-hide - use if you only need to show or hide something (modifies CSS)
ng-if - new in version 1.1.5, use instead of the more verbose ng-switch if you only need to check for a single condition (modifies DOM)
ng-switch - u...
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...
Can I start the iPhone simulator without “Build and Run”?
I want to delete an app in the simulator before I "build and run". How can I start the simulator so I can do the deletion? If I start it by "build and run" I get a long log output that takes a while because of a bug I'm trying to fix. I'd like to avoid that.
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Can media queries resize based on a div element instead of the screen?
...he screen size as the div is just used like a widget within the webpage, and its size can vary.
11 Answers
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Should an Enum start with a 0 or a 1?
...ag enum values of zero unless the value represents "all flags are cleared" and is named appropriately, as prescribed by the next guideline.
✔️ DO name the zero value of flag enums None. For a flag enum, the value must always mean "all flags are cleared."
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What does “atomic” mean in programming?
... written using two separate operations: one that writes the first 32 bits, and a second one which writes the last 32 bits. That means that another thread might read the value of foo, and see the intermediate state.
Making the operation atomic consists in using synchronization mechanisms in order t...
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...
Best practice to mark deprecated code in Ruby?
...a method as deprecated, so the people using it can easily check their code and catch up. In Java you set @Deprecated and everybody knows what this means.
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