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What is an “unwrapped value” in Swift?
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First, you have to understand what an Optional type is. An optional type basically means that the variable can be nil.
Example:
var canBeNil : Int? = 4
canBeNil = nil
The question mark indicates the fact that canBeNil can be nil.
This would not work:...
Monad in plain English? (For the OOP programmer with no FP background)
...ogrammer would understand (without any functional programming background), what is a monad?
19 Answers
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What's “this” in JavaScript onclick?
What does this mean in the script?
8 Answers
8
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What's the best CRLF (carriage return, line feed) handling strategy with Git?
...m in a few..) ; not munging line endings is the safest option. If you know what you are doing, I'd probably use core.autocrlf = input and make exceptions for projects on Windows that you know are sensitive to line endings. As others point out, every decent text editor supports LF endings now. I actu...
What Android tools and methods work best to find memory/resource leaks? [closed]
...lasses. For that you need to handle exception. Rest it works fine. That's what I use in my code and it works fine. Hope this helps.
– hp.android
Nov 21 '11 at 13:27
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What are the benefits of Java's types erasure?
...ypes are to programs as theorems are to proofs.
This correspondence is somewhat profound. We can take logical expressions, and translate them through the correspondence to types. Then if we have a program with the same type signature that compiles, we have proven that the logical expression is uni...
What is the difference between a process and a thread?
What is the technical difference between a process and a thread?
35 Answers
35
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What are the downsides to using Dependency Injection? [closed]
... a pattern here at work and one of our lead developers would like to know: What - if any - are the downsides to using the Dependency Injection pattern?
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What is the difference between a deep copy and a shallow copy?
What is the difference between a deep copy and a shallow copy?
31 Answers
31
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A monad is just a monoid in the category of endofunctors, what's the problem?
.... Here it is in context, which is probably the best place to learn exactly what it means.
But, I'll take a stab. The original sentence is this:
All told, a monad in X is just a monoid in the category of endofunctors of X, with product × replaced by composition of endofunctors and unit set by the i...