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How to get a random number in Ruby
...6). A roll in craps could be simulated with 2 + rand(6) + rand(6).
Finally, if you just need a random float, just call rand with no arguments.
As Marc-André Lafortune mentions in his answer below (go upvote it), Ruby 1.9.2 has its own Random class (that Marc-André himself helped to debug,...
Checking if array is multidimensional or not?
...will recursively count the array. This is particularly useful for counting all the elements of a multidimensional array. count() does not detect infinite recursion.
However this method does not detect array(array()).
share...
C++ catching all exceptions
...
try{
// ...
} catch (...) {
// ...
}
will catch all C++ exceptions, but it should be considered bad design. You can use c++11's new current_exception mechanism, but if you don't have the ability to use c++11 (legacy code systems requiring a rewrite), then you have no name...
use of deleted function std::unique_ptr 编译错误剖析，你可能少了一个st...
use of deleted function std::unique_ptr 编译错误剖析，你可能少了一个std::move编译报错日志如下： usr include c++ 4 7 bits stl_construct h:77:7: error: use of deleted function & 39;std::unique_ptr<_Tp, _Dp>::unique_ptr(const std::unique_p 编译报错日志如下：
/usr/...
Copy data into another table
...the column list for newTable is optional if you are specifying a value for all columns and selecting columns in the same order as newTable's schema):
INSERT INTO newTable (col1, col2, col3)
SELECT column1, column2, column3
FROM oldTable
...
How to display the default iOS 6 share action sheet with available share options?
...he UIActivityViewController stated in the other answer makes this trivial. All you have to do is specify the text/image/URL that you want to share and present the activity view controller modally and iOS will automatically display all applicable sharing services. Examples:
Objective-C
- (void)shar...
Is it true that one should not use NSLog() on production code?
... line number to make it easier to track down log statements.
#define DEBUG_MODE
#ifdef DEBUG_MODE
#define DebugLog( s, ... ) NSLog( @"<%p %@:(%d)> %@", self, [[NSString stringWithUTF8String:__FILE__] lastPathComponent], __LINE__, [NSString stringWithFormat:(s), ##__VA_ARGS__] )
#else
...
What is the colon operator in Ruby?
..." # false
:foo.equal? :foo # true
This makes comparing two symbols really fast (since only a pointer comparison is involved, as opposed to comparing all the characters like you would in a string), plus you won't have a zillion copies of the same symbol floating about.
Also, unlike strings, sy...
When to use static vs instantiated classes
...r BB code to HTML ; it doesn't have a life on its own)
(Yeah, I admit, really really overly-simplified...)
One thing about static methods/classes is that they don't facilitate unit testing (at least in PHP, but probably in other languages too).
Another thing about static data is that only one in...
Set the value of a variable with the result of a command in a Windows batch file
...%a in ('command1 ^| command2') do set VAR=%%a.
– Bill_Stewart
Mar 4 '16 at 19:23
@Bill_Stewart you just saved my day, ...