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What is the difference between & and && in Java?
... @Michu93: One example would be if the second condition is a function call which has a side effect that you always need. Since side effects should usually be avoided, there will be only rare cases where you need that, and I can't think of a realistic example at the moment.
–...
What is the difference between Type and Class?
...primitives are classes (or more exactly structs).
– dalle
Jan 22 '09 at 7:10
4
@dalle: agreed, th...
Is double square brackets [[ ]] preferable over single square brackets [ ] in Bash?
...
[[ has fewer surprises and is generally safer to use. But it is not portable - POSIX doesn't specify what it does and only some shells support it (beside bash, I heard ksh supports it too). For example, you can do
[[ -e $b ]]
to test whether a file exists....
Remove duplicate rows in MySQL
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A really easy way to do this is to add a UNIQUE index on the 3 columns. When you write the ALTER statement, include the IGNORE keyword. Like so:
ALTER IGNORE TABLE jobs
ADD UNIQUE INDEX idx_name (site_id, title, company);
Th...
How to efficiently concatenate strings in go
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If you know the total length of the string that you're going to preallocate then the most efficient way to concatenate strings may be using the builtin function copy. If you don't know the total length before hand, do not use copy, and read the other answers instead.
In my tests, that approa...
Check if a string is html or not
...(c[i].nodeType == 1) return true;
}
return false;
}
The idea is to allow browser DOM parser to decide if provided string looks like an HTML or not. As you can see it simply checks for ELEMENT_NODE (nodeType of 1).
I made a couple of tests and looks like it works:
isHTML('<a>this is a...
Find and restore a deleted file in a Git repository
... of '~1': git checkout <deleting-commit>~1 -- <file-path> ~X allows you to specify X commits before the specified commit, so ~1 is the commit before, ~2 is two commits before, etc
– Nils Luxton
Sep 10 '12 at 15:07
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Downloading a large file using curl
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<?php
set_time_limit(0);
//This is the file where we save the information
$fp = fopen (dirname(__FILE__) . '/localfile.tmp', 'w+');
//Here is the file we are downloading, replace spaces with %20
$ch = curl_init(str_replace(" ","%20...
Can a class member function template be virtual?
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Templates are all about the compiler generating code at compile-time. Virtual functions are all about the run-time system figuring out which function to call at run-time.
Once the run-time system figured out it would need to call a templ...
python pandas: Remove duplicates by columns A, keeping the row with the highest value in column B
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Small note: The cols and take_last parameters are depreciated and have been replaced by the subset and keep parameters. pandas.pydata.org/pandas-docs/version/0.17.1/generated/…
– Jezzamon
...