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Swift: Testing optionals for nil
... nil to move for the next condition. If only nil check is required, remove extra conditions in the following code.
Other than that, if x is not nil, the if closure will be executed and x_val will be available inside. Otherwise the else closure is triggered.
if let x_val = x, x_val > 5 {
//x...
In Python, what happens when you import inside of a function? [duplicate]
...me is expensive. Try running an empty script vs one containing just import string,itertools,fractions,heapq,re,array,bisect,collections,math,os. The first takes an average of 180 ms, and the second 230 ms. So it's not microseconds for starters. It's tens of milliseconds (maybe a disc access happens?...
Check OS version in Swift?
...0 or 11 using if:
let floatVersion = (UIDevice.current.systemVersion as NSString).floatValue
EDIT:
Just found another way to achieve this:
let iOS8 = floor(NSFoundationVersionNumber) > floor(NSFoundationVersionNumber_iOS_7_1)
let iOS7 = floor(NSFoundationVersionNumber) <= floor(NSFoundatio...
Different floating point result with optimization enabled - compiler bug?
...king crusty old 32-bit binaries), because SSE/SSE2 has temporaries with no extra precision. double and float vars in XMM registers are really in IEEE 64-bit or 32-bit format. (Unlike x87, where the registers are always 80-bit, and storing to memory rounds to 32 or 64 bit.)
– ...
Does Swift have documentation generation support?
... Nothing useful.
func doNothing(int: Int, bool: Bool = false) throws -> String {
if unlucky { throw Error.BadLuck }
return "Totally contrived."
}
Syntax for Swift 2 (based on Markdown)
Comment Style
Both /// (inline) and /** */ (block) style comments are supported for producing ...
Looping through localStorage in HTML5 and JavaScript
...u could store a JSON-serialized array:
localStorage.setItem("words", JSON.stringify(["Lorem", "Ipsum", "Dolor"]));
The draft spec claims that any object that supports structured clone can be a value. But this doesn't seem to be supported yet.
EDIT: To load the array, add to it, then store:
var...
How to escape a JSON string to have it in a URL?
...
encodeURIComponent(JSON.stringify(object_to_be_serialised))
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How do I get a raw, compiled SQL query from a SQLAlchemy expression?
...as the caveats that it is only supported for basic types, such as ints and strings, and furthermore if a bindparam() without a pre-set value is used directly, it won’t be able to stringify that either.
The documentation also issues this warning:
Never use this technique with string content r...
detach all packages while working in R
...
invisible(suppressMessages(suppressWarnings(lapply(c("gsl","fBasics","stringr","stringi","Rmpfr"), require, character.only = TRUE))))
invisible(suppressMessages(suppressWarnings(lapply(names(sessionInfo()$loadedOnly), require, character.only = TRUE))))
sessionInfo()
#the above is a...
How to get filename without extension from file path in Ruby
...
Note that double quotes strings escape \'s.
'C:\projects\blah.dll'.split('\\').last
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