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How to define optional methods in Swift protocol?
Is it possible in Swift? If not then is there a workaround to do it?
19 Answers
19
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Is a view faster than a simple query?
...ueries.
Update: At least three people have voted me down on this one. With all due respect, I think that they are just wrong; Microsoft's own documentation makes it very clear that Views can improve performance.
First, simple views are expanded in place and so do not directly contribute to perf...
How to find memory leak in a C++ code/project?
...ory only if you've deleted. In the code below, str acquires a new address with the second allocation. The first address is lost irretrievably, and so are the 30 bytes that it pointed to. Now they're impossible to free, and you have a memory leak:
char* str = new char [30]; // Give str a memory addr...
CSS background opacity with rgba not working in IE 8
I am using this CSS for background opacity of a <div> :
15 Answers
15
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SQL Server add auto increment primary key to existing table
As the title, I have an existing table which is already populated with 150000 records. I have added an Id column (which is currently null).
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Build an iOS app without owning a mac? [closed]
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Let me tell you step by step few years back I was in same situation.
So We have two Phases
iPhone/iPad (iOS) app development
iPhone/iPad (iOS) app development and Publish to iTunes Store
1. iPhone/iPad (iOS) app development
So If you just want to develop iOS apps you don't want...
Syntax behind sorted(key=lambda: …)
I don't quite understand the syntax behind the sorted() argument:
9 Answers
9
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Why can I add named properties to an array as if it were an object?
... javascript is an object, so you can "abuse" an Array object by setting arbitrary properties on it. This should be considered harmful though. Arrays are for numerically indexed data - for non-numeric keys, use an Object.
Here's a more concrete example why non-numeric keys don't "fit" an Array:
var...
Flushing footer to bottom of the page, twitter bootstrap
I am generally familiar with the technique of flushing a footer using css.
34 Answers
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How to fix HTTP 404 on Github Pages?
Here is my GitHub repository on the gh-pages branch.
Everything looks good, I have my index.html , my CSS, JS and pictures folders.
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