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Max return value if empty query
... .Select(x => x.ShoeSize)
.DefaultIfEmpty(0)
.Max();
The zero in DefaultIfEmpty is not necessary.
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Why do you need to put #!/bin/bash at the beginning of a script file?
...helps some editors like Vim determine the language for syntax highlighting if the file doesn't have an extension. Without the shebang, Vim will display a bash script the same as plain text file.
– Aaron Blenkush
Dec 10 '13 at 21:16
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C++STL容器使用经验总结 - C/C++ - 清泛网 - 专注C/C++及内核技术
...对象：
如果容器是vector、string或deque，则使用erase-remove_if习惯用法。
如果容器是list，则使用list::remove_if。
如果容器是一个标准关联容器，则使用remove_copy_if和swap，或者写一个循环遍历容器的元素，记住当把迭代器传给erase时...
Is duplicated code more tolerable in unit tests?
...eems there is a trade-off between tests' readability and maintainability. If I leave duplicated code in unit tests, they're more readable, but then if I change the SUT , I'll have to track down and change each copy of the duplicated code.
...
Transferring files over SSH [closed]
...'re saying secure copy ./styles/, but not where to copy it to.
Generally, if you want to download, it will go:
# download: remote -> local
scp user@remote_host:remote_file local_file
where local_file might actually be a directory to put the file you're copying in. To upload, it's the opposit...
How to map atan2() to degrees 0-360
...rtable with this notation, and without the conversion to degrees built in: if(x>0) {radians = x;} else {radians = 2*PI + x;} so we are just adding 2PI to the result if it is less than 0.
– David Doria
Sep 25 '12 at 19:05
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How can I get the line number which threw exception?
...
If you need the line number for more than just the formatted stack trace you get from Exception.StackTrace, you can use the StackTrace class:
try
{
throw new Exception();
}
catch (Exception ex)
{
// Get stack trace ...
php is null or empty?
...
What you're looking for is:
if($variable === NULL) {...}
Note the ===.
When use ==, as you did, PHP treats NULL, false, 0, the empty string, and empty arrays as equal.
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Simplest SOAP example
...';
xmlhttp.onreadystatechange = function () {
if (xmlhttp.readyState == 4) {
if (xmlhttp.status == 200) {
alert(xmlhttp.responseText);
// alert('done. use firebug/console to see network response');
...
Why can't I push to this bare repository?
...e are no commits in "bare". This is a problem with the first commit only, if you create the repos in the order (bare,alice). Try doing:
git push --set-upstream origin master
This would only be required the first time. Afterwards it should work normally.
As Chris Johnsen pointed out, you would...