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Reference: What is variable scope, which variables are accessible from where and what are “undefined
...pplication. The variable $foo has a certain scope within which it is valid and only code in the same scope has access to the variable.
How is a scope defined in PHP?
Very simple: PHP has function scope. That's the only kind of scope separator that exists in PHP. Variables inside a function are onl...
How to delete history of last 10 commands in shell?
Commands follows
18 Answers
18
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Is there something like RStudio for Python? [closed]
In RStudio, you can run parts of code in the code editing window, and the results appear in the console.
10 Answers
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How do I undo the most recent local commits in Git?
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Undo a commit and redo
$ git commit -m "Something terribly misguided" # (1)
$ git reset HEAD~ # (2)
<< edit files as necessary >> # (3)
$ git add...
Call ASP.NET function from JavaScript?
I'm writing a web page in ASP.NET. I have some JavaScript code, and I have a submit button with a click event.
20 Answers
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What's Up with Logging in Java? [closed]
... the integrated solution); especially valid if you're an API/Framework/OSS and you rely on other packages that use Commons Logging.
Commons Logging because you don't want to "lock down" to a particular logging framework (so instead you lock down to what Commons Logging gives you instead) - I don't t...
Why are C# 3.0 object initializer constructor parentheses optional?
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This question was the subject of my blog on September 20th 2010. Josh and Chad's answers ("they add no value so why require them?" and "to eliminate redundancy") are basically correct. To flesh that out a bit more:
The feature of allowing you to elide the argument list as part of the "larger f...
Why do I need to override the equals and hashCode methods in Java?
...n conjunction with all hash-based collections, including HashMap, HashSet, and Hashtable.
Let's try to understand it with an example of what would happen if we override equals() without overriding hashCode() and attempt to use a Map.
Say we have a class like this and that two objects of MyClass are...
How to throw an exception in C?
...tion (or other notification error form the CPU if there is)(How processor handles the case of division by zero).
Exceptions are defined in C++ and other languages though. Exception handling in C++ is specified in the C++ standard "S.15 Exception handling", there is no equivalent section in the C st...
Why can't decimal numbers be represented exactly in binary?
...e the == operator to compare it to another floating-point number. I understand the principles behind floating-point representation.
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