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Differences between Perl and PHP [closed]
...$foo ||= 'default' to set $foo to a value if it's not already set. The shortest way of doing this in PHP is $foo = isset($foo) ? $foo : 'default'; (Update, in PHP 7.0+ you can do $foo = $foo ?? 'default')
Perl variable names indicate built-in type, of which Perl has three, and the type specifier is ...
Unable to execute dex: GC overhead limit exceeded in Eclipse
...4-bit JVM. If you're on a 64 bit JVM, you can safely set it to anything smaller than your RAM size minus overhead for OS/other applications. On a 32 bit VM, you'll want to keep it smaller than about 1500M (on Linux) or 1100M (on Windows) because the VM needs to allocate contiguous address space, a...
Rails 3 - can't install pg gem
...1/bin/pg_config for 9.1.x) and the development headers. It's what I use to test the pg gem in development.
– Michael Granger
Mar 12 '12 at 23:53
...
Show Youtube video source into HTML5 video tag?
... some expire stuff. I don't know how long the src string will work.
Still testing myself.
Edit (July 28, 2011): Note that this video src is specific to the browser you use to retrieve the page source. I think Youtube generates this HTML dynamically (at least currently) so in testing if I copy in ...
How do I create an average from a Ruby array?
...void integer division or your results will be wrong. Also, this isn't generally applicable to every possible element type (obviously, an average only makes sense for things that can be averaged). But if you want to go that route, use this:
class Array
def sum
inject(0.0) { |result, el| result...
How to get name of exception that was caught in Python?
...n't want to catch particular exceptions known in advance. I want to catch all exceptions.
– Rob Bednark
Apr 27 '18 at 16:10
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How does an underscore in front of a variable in a cocoa objective-c class work?
...to-generated accessor (for the property) knows which ivar to use. Specifically, in your implementation file, your synthesize should look like this:
@synthesize missionName = _missionName;
More generically, this is:
@synthesize propertyName = _ivarName;
...
PowerShell script to return versions of .NET Framework on a machine?
...t). It also outputs both Client and Full on 4.0 (if you have them both installed):
Get-ChildItem 'HKLM:\SOFTWARE\Microsoft\NET Framework Setup\NDP' -recurse |
Get-ItemProperty -name Version,Release -EA 0 |
Where { $_.PSChildName -match '^(?!S)\p{L}'} |
Select PSChildName, Version, Release
Based o...
Regular cast vs. static_cast vs. dynamic_cast [duplicate]
...ncludes a complete Base object.
class MyBase
{
public:
virtual void test() {}
};
class MyChild : public MyBase {};
int main()
{
MyChild *child = new MyChild();
MyBase *base = dynamic_cast<MyBase*>(child); // ok
}
The next example attempts to convert a MyBase pointer to a MyChi...
What's a correct and good way to implement __hash__()?
...be integers, and there aren't too many of them, I suppose you could potentially run slightly faster with some home-rolled hash, but it likely wouldn't be as well distributed. hash((self.attr_a, self.attr_b, self.attr_c)) is going to be surprisingly fast (and correct), as creation of small tuples is ...