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Is there an “exists” function for jQuery?
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In JavaScript, everything is 'truthy' or 'falsy', and for numbers 0 means false, everything else true. So you could write:
if ($(selector).length)
You don't need that >0 part.
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What is the difference between vmalloc and kmalloc?
I've googled around and found most people advocating the use of kmalloc , as you're guaranteed to get contiguous physical blocks of memory. However, it also seems as though kmalloc can fail if a contiguous physical block that you want can't be found.
What are the advantages of having a contig...
Java: Path vs File
...hat said, java.nio.file.Path is part of the more modern java.nio.file lib, and does everything java.io.File can, but generally in a better way, and more.
For new projects, use Path.
And if you ever need a File object for legacy, just call Path#toFile()
Migrating from File to Path
This Oracle pa...
JavaScript variables declare outside or inside loop?
...rmance, in JavaScript or ActionScript.
var is a directive for the parser, and not a command executed at run-time. If a particular identifier has been declared var once or more anywhere in a function body(*), then all use of that identifier in the block will be referring to the local variable. It ma...
Objective-C: Where to remove observer for NSNotification?
I have an objective C class. In it, I created a init method and set up a NSNotification in it
14 Answers
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What is the difference between include and require in Ruby?
My question is similar to " What is the difference between include and extend in Ruby? ".
11 Answers
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“Comparison method violates its general contract!”
...de throw an exception, "Comparison method violates its general contract!", and how do I fix it?
11 Answers
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Using sed and grep/egrep to search and replace
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Use this command:
egrep -lRZ "\.jpg|\.png|\.gif" . \
| xargs -0 -l sed -i -e 's/\.jpg\|\.gif\|\.png/.bmp/g'
egrep: find matching lines using extended regular expressions
-l: only list matching filenames
-R: search recursively th...
iPhone app in landscape mode, 2008 systems
Please note that this question is from 2008 and now is of only historic interest.
8 Answers
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How do I get a human-readable file size in bytes abbreviation using .NET?
... to do it, but it's easier to read if you are not familiar with log maths, and should be fast enough for most scenarios.
string[] sizes = { "B", "KB", "MB", "GB", "TB" };
double len = new FileInfo(filename).Length;
int order = 0;
while (len >= 1024 && order < sizes.Length - 1) {
o...