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?: operator (the 'Elvis operator') in PHP
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It evaluates to the left operand if the left operand is truthy, and the right operand otherwise.
In pseudocode,
foo = bar ?: baz;
roughly resolves to
foo = bar ? bar : baz;
or
if (bar) {
foo = bar;
} else {
foo = baz;
}
with the differe...
Linq code to select one item
...ion methods directly like:
var item = Items.First(i => i.Id == 123);
And if you don't want to throw an error if the list is empty, use FirstOrDefault which returns the default value for the element type (null for reference types):
var item = Items.FirstOrDefault(i => i.Id == 123);
if (ite...
Get the first element of each tuple in a list in Python [duplicate]
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@Creak - x,_ is just using tuple unpacking. And you are right, the documentation on this is hard to come by. I found this link and this one which should explain how it works. Also, the _ is just a normal variable. I could have done x,y and got the same results. How...
How do I check if a directory exists? “is_dir”, “file_exists” or both?
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considering it takes post input and uses it as-is, plus makes 0777 dir, prolly not that safe at all ;P
– sEver
Aug 20 '13 at 16:45
2
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How to quickly edit values in table in SQL Server Management Studio?
... top 200, you can view the SQL pane - either by right clicking in the grid and choosing Pane->SQL or by the button in the upper left. This will allow you to write a custom query to drill down to the row(s) you want to edit.
But ultimately mgmt studio isn't a data entry/update tool which is why ...
Are there best practices for (Java) package organization? [closed]
...y a heated discussion. Below are some simple guidelines for package naming and structuring:
Follow java package naming conventions
Structure your packages according to their functional role as well as their business role
Break down your packages according to their functionality or modules. e.g. ...
How to destroy an object?
...ly destroy an object.
It will stay there, however if you unset the object and your script pushes PHP to the memory limits the objects not needed will be garbage collected. I would go with unset() (as opposed to setting it to null) as it seems to have better performance (not tested but documented on...
How to reference a .css file on a razor view?
... type="text/css" />
@RenderSection("Styles", false)
</head>
and if I need some view specific styles I define the Styles section in each view:
@section Styles {
<link href="@Url.Content("~/Styles/view_specific_style.css")" rel="stylesheet" type="text/css" />
}
Edit: It's u...
Python string.join(list) on object array rather than string array
...duce was the one that was removed, because it usually left people guessing and thus wasn't "pythonic". map on the other hand is not an issue.
– PascalVKooten
Oct 12 '15 at 16:28
1
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What does the “-U” option stand for in pip install -U
Despite a ton of Googling, I can't find any docs for pip's command line options/arguments. What does pip install -U mean? Does anyone have a link to a list of pip's options and arguments?
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