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What does $$ (dollar dollar or double dollar) mean in PHP?
... resolves a variable by that string.
So, consider this example
$inner = "foo";
$outer = "inner";
The variable:
$$outer
would equal the string "foo"
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Optional Methods in Java Interface
...lections are an exception" suggests a very fuzzy understanding of what's really going on here.
It's important to realize that there are sort of two levels of conforming to an interface:
What the Java language can check. This pretty much just boils down to: is there some implementation for each of...
What is the difference between parseInt(string) and Number(string) in JavaScript? [duplicate]
...dendum to @sjngm's answer:
They both also ignore whitespace:
var foo = " 3 "; console.log(parseInt(foo)); // 3
console.log(Number(foo)); // 3
It is not exactly correct. As sjngm wrote parseInt parses string to first number. It is true. But the problem is when you want to parse ...
Split by comma and strip whitespace in Python
...x.strip() for x in text.split('.') if x != '']
– RandallShanePhD
Jul 28 '17 at 19:41
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How to access array elements in a Django template?
...o template is used for four different notations in Python. In a template, foo.bar can mean any of:
foo[bar] # dictionary lookup
foo.bar # attribute lookup
foo.bar() # method call
foo[bar] # list-index lookup
It tries them in this order until it finds a match. So foo.3 wi...
How is the “greater than” or “>” character used in CSS?
...a CSS child selector. P > SPAN means applying the style that follows to all SPAN tags that are children of a P tag.
Note that "child" means "immediate descendant", not just any descendant. P SPAN is a descendant selector, applying the style that follows to all SPAN tags that are children of a P ...
Remove a fixed prefix/suffix from a string in Bash
... argument list, and
There are no spaces in $prefix and $suffix
It's generally good practice to quote a string on the command line because even if it contains spaces it will be presented to the command as a single argument. We quote $prefix and $suffix for the same reason: each edit command to sed ...
AngularJS: How to clear query parameters in the URL?
...to do that I need to redirect the user to a LinkedIn URL which contains a callback redirect_uri parameter which will tell LinkedIn to redirect the user back to my webapp and include a "code" query param in the URL. It's a traditional Oauth 2.0 flow.
...
How to split one string into multiple variables in bash shell? [duplicate]
...how you can read each individual character into array elements:
$ read -a foo <<<"$(echo "ABCDE-123456" | sed 's/./& /g')"
Dump the array:
$ declare -p foo
declare -a foo='([0]="A" [1]="B" [2]="C" [3]="D" [4]="E" [5]="-" [6]="1" [7]="2" [8]="3" [9]="4" [10]="5" [11]="6")'
If there...
What does it mean to hydrate an object?
... you probably don't need to deal with hydration explicitly. You would typically use deserialization instead so you can write less code. Some data access APIs don't give you this option, and in those cases you'd also have to explicitly call the hydration step yourself.
For a bit more detail on the c...