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What is an “unwrapped value” in Swift?
...ar cantBeNil : Int = 4
cantBeNil = nil // can't do this
To get the value from your variable if it is optional, you have to unwrap it. This just means putting an exclamation point at the end.
var canBeNil : Int? = 4
println(canBeNil!)
Your code should look like this:
let optionalSquare: Square?...
Android AsyncTask threads limits?
... database in the phone. For all those operations (updates, retrieving data from db and etc.) I use async tasks. As up till now I didn't see why I shouldn't use them, but recently I experienced that if I do some operations some of my async tasks simply stop on pre-execute and don't jump to doInBackgr...
Safest way to convert float to integer in python?
...t representations are possible where int(floor(2.3)) might be 1.
To quote from Wikipedia,
Any integer with absolute value less than or equal to 224 can be exactly represented in the single precision format, and any integer with absolute value less than or equal to 253 can be exactly represented...
Explain Python entry points?
...d I wanted it to make available a "cursive" command that someone could run from the command line, like:
$ cursive --help
usage: cursive ...
The way to do this is define a function, like maybe a "cursive_command" function in cursive/tools/cmd.py that looks like:
def cursive_command():
args = ...
Understanding __get__ and __set__ and Python descriptors
... that great).
A descriptor is defined on a class, but is typically called from an instance. When it's called from an instance both instance and owner are set (and you can work out owner from instance so it seems kinda pointless). But when called from a class, only owner is set – which is why it's...
When should we use mutex and when should we use semaphore
... must happen in the same thread later on.
e.g.: If you are deleting a node from a global linked list, you do not want another thread to muck around with pointers while you are deleting the node. When you acquire a mutex and are busy deleting a node, if another thread tries to acquire the same mutex,...
Convert a 1D array to a 2D array in numpy
...B = np.reshape(A, (-1, 2))
where -1 infers the size of the new dimension from the size of the input array.
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What's the meaning of “=>” (an arrow formed from equals & greater than) in JavaScript?
...below).
You can read more in the Mozilla documentation on arrow functions.
From the Mozilla documentation:
An arrow function expression (also known as fat arrow function) has a shorter syntax compared to function expressions and lexically binds the this value (does not bind its own this, arguments,...
CSS scrollbar style cross browser [duplicate]
...
Everyone would like it. The single smart idea coming from the IE era ?
– Ben
Jan 15 '14 at 16:36
...
Accessing member of base class
See the inheritance example from the playground on the TypeScript site:
2 Answers
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