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Best way to detect that HTML5 is not supported
... browser does not support the HTML5 <canvas> tag is to embed some fallback content like:
8 Answers
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HTML Input=“file” Accept Attribute File Type (CSV)
...rked for me in firefox, chrome and opera on mac. only .csv did not work in all browsers.
– tmas
Feb 15 '16 at 15:22
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classical inheritance vs prototypal inheritance in javascript
...n: The representation of real world things in computer programs.
Theoretically an abstraction is defined as "a general concept formed by extracting common features from specific examples". However for the sake of this explanation we're going to use the aforementioned definition instead.
Now some o...
What does the exclamation mark do before the function?
...s just a function declaration. You would need an invocation, foo(), to actually run the function.
Now, when we add the seemingly innocuous exclamation mark: !function foo() {} it turns it into an expression. It is now a function expression.
The ! alone doesn't invoke the function, of course, but w...
java: (String[])List.toArray() gives ClassCastException
...hat type of array to create.
use
toArray(new String[v2.size()]);
which allocates the right kind of array (String[] and of the right size)
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How do I “Add Existing Item” an entire directory structure in Visual Studio?
I have a free standing set of files not affiliated with any C# project at all that reside in a complicated nested directory structure.
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Why shouldn't I use PyPy over CPython if PyPy is 6.3 times faster?
...to mention, has tenuous support for C extensions. It has support, but typically at slower-than-Python speeds and it's iffy at best. Hence a lot of modules simply require CPython. PyPy doesn't support numpy PyPy now supports numpy. Some extensions are still not supported (Pandas, SciPy, etc.), take a...
How to calculate “time ago” in Java?
In Ruby on Rails, there is a feature that allows you to take any Date and print out how "long ago" it was.
30 Answers
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Using ls to list directories and their total sizes
...possible to use ls in Unix to list the total size of a sub-directory and all its contents as opposed to the usual 4K that (I assume) is just the directory file itself?
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Check number of arguments passed to a Bash script
...nd regex matching.
The following example checks if arguments are valid. It allows a single argument or two.
[[ ($# -eq 1 || ($# -eq 2 && $2 == <glob pattern>)) && $1 =~ <regex pattern> ]]
For pure arithmetic expressions, using (( )) to some may still be better, but they ...