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Swift: Testing optionals for nil
I'm using Xcode 6 Beta 4. I have this weird situation where I cannot figure out how to appropriately test for optionals.
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How to save an HTML5 Canvas as an image on a server?
...="200"></canvas>
<script>
var canvas = document.getElementById('myCanvas');
var context = canvas.getContext('2d');
// begin custom shape
context.beginPath();
context.moveTo(170, 80);
context.bezierCurveTo(130, 100, 130, 150, 230, 150);
context.bezierCurveTo(250, 180, 32...
Can I see changes before I save my file in Vim?
I use Vim.
I open a file. I edit it and I want to see what I've edited before I save it.
14 Answers
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WPF: Setting the Width (and Height) as a Percentage Value
Say I want a TextBlock to have its Width equal to it's Parent container's Width (ie, stretch from side to side) or a percentage of it's Parent Container Width , how can I accomplish this in XAML without specifying absolute values?
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Java switch statement: Constant expression required, but it IS constant
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I understand that the compiler needs the expression to be known at compile time to compile a switch, but why isn't Foo.BA_ constant?
While they are constant from the perspective of any code that executes after the fields have been initialized, they are not a compile time consta...
PHP mkdir: Permission denied problem
I am trying to create a directory with PHP mkdir function but I get an error as follows: Warning: mkdir() [function.mkdir]: Permission denied in ... . How to settle down the problem?
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Creating an array of objects in Java
I am new to Java and for the time created an array of objects in Java.
8 Answers
8
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What does $.when.apply($, someArray) do?
I'm reading about Deferreds and Promises and keep coming across $.when.apply($, someArray) . I'm a little unclear on what this does exactly, looking for an explanation that one line works exactly (not the entire code snippet). Here's some context:
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Direct vs. Delegated - jQuery .on()
I am trying to understand this particular difference between the direct and delegated event handlers using the jQuery .on() method . Specifically, the last sentence in this paragraph:
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Database Design for Tagging
How would you design a database to support the following tagging features:
12 Answers
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