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How to compare strings in Bash
... do we use quotes around $x?
You want the quotes around $x, because if it is empty, your Bash script encounters a syntax error as seen below:
if [ = "valid" ]; then
Non-standard use of == operator
Note that Bash allows == to be used for equality with [, but this is not standard.
Use either t...
Benefits of using the conditional ?: (ternary) operator
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I would basically recommend using it only when the resulting statement is extremely short and represents a significant increase in conciseness over the if/else equivalent without sacrificing readability.
Good example:
int result = Check() ? 1 : 0;
Bad example:
int result = FirstCheck() ? 1 ...
What does void mean in C, C++, and C#?
... to get the fundamentals on where the term " void " comes from, and why it is called void. The intention of the question is to assist someone who has no C experience, and is suddenly looking at a C-based codebase.
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How to use LocalBroadcastManager?
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I'll answer this anyway. Just in case someone needs it.
ReceiverActivity.java
An activity that watches for notifications for the event named "custom-event-name".
@Override
public void onCreate(Bundle savedInstanceState) {
...
// ...
Why should I declare a virtual destructor for an abstract class in C++?
I know it is a good practice to declare virtual destructors for base classes in C++, but is it always important to declare virtual destructors even for abstract classes that function as interfaces? Please provide some reasons and examples why.
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What is the difference between using IDisposable vs a destructor in C#?
When would I implement IDispose on a class as opposed to a destructor? I read this article , but I'm still missing the point.
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How to determine the current shell I'm working on
...ote that all three approaches can be fooled if the executable of the shell is /bin/sh, but it's really a renamed bash, for example (which frequently happens).
Thus your second question of whether ps output will do is answered with "not always".
echo $0 - will print the program name... which in th...
What is the non-jQuery equivalent of '$(document).ready()'?
What is the non-jQuery equivalent of $(document).ready() ?
9 Answers
9
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Polymorphism in C++
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Understanding of / requirements for polymorphism
To understand polymorphism - as the term is used in Computing Science - it helps to start from a simple test for and definition of it. Consider:
Type1 x;
Type2 y;
f(x);
f(y);
Here, f() is to perform ...
Difference between string and text in rails?
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The difference relies in how the symbol is converted into its respective column type in query language.
with MySQL :string is mapped to VARCHAR(255)
- http://guides.rubyonrails.org/migrations.html
:string | VARCHAR | :limit ...