How does Swift know the English alphabet? [duplicate] - swift

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How String Comparison happens in Swift
(4 answers)
What does it mean that string and character comparisons in Swift are not locale-sensitive?
(3 answers)
Closed 5 years ago.
Documentation > Swift > ClosedRange
let values = "a"..."z"
print(values.contains("c")) //true
Could someone please explain why this prints true?

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Flutter How to not show the [] Brackets of a list when being displayed as a text? [duplicate]

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Display a list of integers as a String
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Closed 3 years ago.
I am trying to display a list rendered in text. But when I do I see the []
I have tried the following.
Text(hashList.toString().replaceAll("(^\\[|\\])", ""))
Brackets are still there.
You can do it like this
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Text(hashList.join(','))

Reduce a double in swift [duplicate]

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Closed 3 years ago.
I am trying to reduce the amount of characters in a double. How Would I reduce this:
59.5220000
to
59.5
this in swift?
A double doesn't have characters. A string rendering of it does. Rather than using the standard String() initializer (which is really only for development use, it's terrible for end-users), use NumberFormatter.
perhaps use a formatted string?
let str = String(format: "%.2f", 59.5220000)

Swift 4 regex custom validation [duplicate]

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Closed 4 years ago.
i need some help to write correct regex validation. I want password with no spaces, min. 6 symbols, doesn't matter numbers or letters or symbols. Alphabet a-zA-Z and а-яА-Я(RU). How i can do that?
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You can take a look at this link

How can I evaluate bool/arithmetic expression in Swift? [duplicate]

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Closed 6 years ago.
How can I eval a string in Swift?
My strings are composed by numbers and logic operators.
Some examples are:
"2+2"
"2%2"
"2+2"
"2=3"
"2>3"
"2/5"
I've thought, if is too complex to write a function to do this, to parse a string and execute that as external process in bin/bash process than read a result. Any ideas?
Other questions, like this, are solution if there are only arithmetics operators. In my cases appears bool operators that returns error in NSExpression eval.

See what characters are in an NSCharacterSet [duplicate]

This question already has answers here:
NSArray from NSCharacterSet
(9 answers)
Closed 7 years ago.
When I'm trying
print(NSCharacterSet.URLQueryAllowedCharacterSet())
it prints
<__NSCFCharacterSet: 0x1759b900>
How do I make it more informative?
You can get a representation of the character set using bitmapRepresentation which could be queried. Or you could do basically the same thing with a loop over all characters and using characterIsMember:. The output is potentially big...
There isn't really a simple option or a generic concise output to what you're asking for. It isn't a common requirement.