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Blocks and yields in Ruby
...trary segments of code.
When a method expects a block, it invokes it by calling the yield function.
This is very handy, for instance, to iterate over a list or to provide a custom algorithm.
Take the following example:
I'm going to define a Person class initialized with a name, and provide a ...
Can an AngularJS controller inherit from another controller in the same module?
... the child controller injects the scope of the parent controller my $scope.AllMembers array get's populated twice as the parent controller causes it to run, then the child controller causes it to run again. Is there any way to prevent that?
– Ryan Mann
Jul 15 ...
What is the difference between Class.getResource() and ClassLoader.getResource()?
...esource paths are always deemed to be absolute.
So the following are basically equivalent:
foo.bar.Baz.class.getResource("xyz.txt");
foo.bar.Baz.class.getClassLoader().getResource("foo/bar/xyz.txt");
And so are these (but they're different from the above):
foo.bar.Baz.class.getResource("/data/x...
Co-variant array conversion from x to y may cause run-time exception
...js[0] = new Foo(); // again legal, with runtime exception
In C#, you are allowed to reference an array of objects (in your case, LinkLabels) as an array of a base type (in this case, as an array of Controls). It is also compile time legal to assign another object that is a Control to the array. Th...
Ruby class instance variable vs. class variable
...n store something common to that class without having sub-classes automatically also get them (and vice-versa). With class variables, you have the convenience of not having to write self.class from an instance object, and (when desirable) you also get automatic sharing throughout the class hierarchy...
Checking if an instance's class implements an interface?
...onstruct() is:
public function __construct() {
$tmp = array(
'foo' => 'bar',
'this' => 'that'
);
$in = in_array('those', $tmp);
}
These tests are based on this simple code.
share
...
How can I declare and use Boolean variables in a shell script?
......
if [ "$the_world_is_flat" = true ] ; then
echo 'Be careful not to fall off!'
fi
Original Answer
Caveats: https://stackoverflow.com/a/21210966/89391
the_world_is_flat=true
# ...do something interesting...
if $the_world_is_flat ; then
echo 'Be careful not to fall off!'
fi
From: Usi...
Why does ++[[]][+[]]+[+[]] return the string “10”?
...array ([]). Due to references it's wrong to say [[]][0] === [], but let's call the inner array A to avoid the wrong notation.
++ before its operand means “increment by one and return the incremented result”. So ++[[]][0] is equivalent to Number(A) + 1 (or +A + 1).
Again, we can simplify the me...
Staging Deleted files
Say I have a file in my git repository called foo .
9 Answers
9
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Assigning default values to shell variables with a single command in bash
...
Very close to what you posted, actually:
FOO=${VARIABLE:-default} # If variable not set or null, use default.
Or, which will assign default to VARIABLE as well:
FOO=${VARIABLE:=default} # If variable not set or null, set it to default.
...