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javascript set a variable if undefined
... // false
// Equivalent to
a = a ?? true
Object/Array Examples
let x = ["foo"]
let y = { foo: "fizz" }
x[0] ??= "bar" // "foo"
x[1] ??= "bar" // "bar"
y.foo ??= "buzz" // "fizz"
y.bar ??= "buzz" // "buzz"
x // Array [ "foo", "bar" ]
y // Object { foo: "fizz", bar: "buzz" }
??= Browser Su...
SVN change username
I found a lot of examples on how to change the username for specific revisions and so on.
11 Answers
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What's an elegant way to conditionally add a class to an HTML element in a view?
...sses where the boolean value evaluated to true.
Sample Usage
class_names(foo: true, bar: false, baz: some_truthy_variable)
# => "foo baz"
Other Use Cases
This helper can be used within ERB tags or with Rails helpers such as link_to.
<div class="<%= class_string(ok: @success) %>">...
Please explain the exec() function and its family
...swered Nov 17 '10 at 13:46
Fred FooFred Foo
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Easiest way to pass an AngularJS scope variable from directive to controller?
..."MyCtrl">
<h2>Parent Scope</h2>
<input ng-model="foo"> <i>// Update to see how parent scope interacts with component scope</i>
<br><br>
<!-- attribute-foo binds to a DOM attribute which is always
a string. That is why we are wra...
Are there benefits of passing by pointer over passing by reference in C++?
...less chance for bugs". When inspecting the call site and the reader sees "foo( &s )" it is immediately clear that s may be modified. When you read "foo( s )" it is not at all clear if s may be modified. This is a major source of bugs. Perhaps there is less chance of a certain class of bugs, ...
How can you diff two pipelines in Bash?
...
A one-line with 2 tmp files (not what you want) would be:
foo | bar > file1.txt && baz | quux > file2.txt && diff file1.txt file2.txt
With bash, you might try though:
diff <(foo | bar) <(baz | quux)
foo | bar | diff - <(baz | quux) # or only use...
How do I write good/correct package __init__.py files
... start. I think it's best to leave __init__.py files empty.
for example:
foo.py - contains classes related to foo such as fooFactory, tallFoo, shortFoo
then the app grows and now it's a whole folder
foo/
__init__.py
foofactories.py
tallFoos.py
shortfoos.py
mediumfoos.py
...
MongoDB: update every document on one field
I have a collected named foo hypothetically.
4 Answers
4
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How can I indent multiple lines in Xcode?
When I select multiple lines of code and want to indent them as usual with TAB key, it just deletes them all. I come from Eclipse where I always did it that way. How's that done in Xcode? I hope not line by line ;)
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