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Why '&&' and not '&'?
...(CanExecute() && CanSave())
{
}
If CanExecute returns false, the complete expression will be false, regardless of the return value of CanSave. Because of this, CanSave is not executed.
This is very handy in the following circumstance:
string value;
if(dict.TryGetValue(key, out value) &am...
Split List into Sublists with LINQ
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Design patterns or best practices for shell scripts [closed]
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I wrote quite complex shell scripts and my first suggestion is "don't". The reason is that is fairly easy to make a small mistake that hinders your script, or even make it dangerous.
That said, I don't have other resources to pass you but...
Mimicking sets in JavaScript?
...ion 3: Add 'A' to the list if it wasn't already there
obj[A] = true;
For completeness, the test for whether A is in the list is a little safer with this:
if (Object.prototype.hasOwnProperty.call(obj, A))
// put code here
}
because of potential conflict between built-in methods and/or properti...
How much faster is C++ than C#?
...any cases. This is mainly due to the more advanced JIT optimizations being complicated to implement, and the really cool ones are only arriving just now.
So C++ is faster, in many cases. But this is only part of the answer. The cases where C++ is actually faster, are highly optimized programs, wher...
Spring MVC: How to perform validation?
...have a null name, result.hasErrors() will be true.
Method 2 : If you have complex validation (like big business validation logic, conditional validation across multiple fields, etc.), or for some reason you cannot use method 1, use manual validation. It is a good practice to separate the controller...
#pragma once vs include guards? [duplicate]
I'm working on a codebase that is known to only run on windows and be compiled under Visual Studio (it integrates tightly with excel so it's not going anywhere). I'm wondering if I should go with the traditional include guards or use #pragma once for our code. I would think letting the compiler de...
How can I declare and use Boolean variables in a shell script?
...l not to fall off!'
fi
Original Answer
Caveats: https://stackoverflow.com/a/21210966/89391
the_world_is_flat=true
# ...do something interesting...
if $the_world_is_flat ; then
echo 'Be careful not to fall off!'
fi
From: Using boolean variables in Bash
The reason the original answer is i...
Create the perfect JPA entity [closed]
...write this down for personal use.
I would not mind however for anyone to comment on it or to tell me where I'm wrong.
4 A...
Arrays, heap and stack and value types
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LOL, always the nit-picker, Mr. Lippert. :) I feel compelled to point out that with the exception of your latter two cases, the so-called "locals" cease to be locals at compile time. The implementation raises them to the status of class members, which is the only reason they...