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How can I remove a flag in C?
...ation of the flag you want to unset. A Bitwise NOT inverts every bit (i.e. 0 => 1, 1 => 0).
flags = flags & ~MASK; or flags &= ~MASK;.
Long Answer
ENABLE_WALK = 0 // 00000000
ENABLE_RUN = 1 // 00000001
ENABLE_SHOOT = 2 // 00000010
ENABLE_SHOOTRUN = 3 // 00000011
value ...
How to validate an e-mail address in swift?
...ValidEmail(_ email: String) -> Bool {
let emailRegEx = "[A-Z0-9a-z._%+-]+@[A-Za-z0-9.-]+\\.[A-Za-z]{2,64}"
let emailPred = NSPredicate(format:"SELF MATCHES %@", emailRegEx)
return emailPred.evaluate(with: email)
}
for versions of Swift earlier than 3.0:
func isValidEmail(e...
Delete element in a slice
... arguments to a variadic function.
So what this line does:
a = append(a[:0], a[1:]...)
is essentially:
a = append(a[:0], a[1], a[2])
Now, you may be wondering, why not just do
a = append(a[1:]...)
Well, the function definition of append is
func append(slice []Type, elems ...Type) []Type
...
Putting an if-elif-else statement on one line?
...st likely violate PEP-8 where it is mandated that lines should not exceed 80 characters in length.
It's also against the Zen of Python: "Readability counts". (Type import this at the Python prompt to read the whole thing).
You can use a ternary expression in Python, but only for expressions, not f...
What is “entropy and information gain”?
...
1051
I assume entropy was mentioned in the context of building decision trees.
To illustrate, imag...
Shuffle two list at once with same order
...
– Jaroslav Klimčík
Apr 25 '14 at 10:15
4
(noob question) - what does the * mean?
...
Position of least significant bit that is set
... position of the least significant bit that is set in an integer, e.g. for 0x0FF0 it would be 4.
22 Answers
...
What is the most efficient string concatenation method in python?
... |
edited May 11 '16 at 7:04
Quentin Pradet
4,28622 gold badges2626 silver badges4040 bronze badges
answ...
Does the ternary operator exist in R?
...
306
As if is function in R and returns the latest evaluation, if-else is equivalent to ?:.
> a ...
How to test valid UUID/GUID?
... first character of the third block).
Therefore to validate a UUID...
/^[0-9a-f]{8}-[0-9a-f]{4}-[0-5][0-9a-f]{3}-[089ab][0-9a-f]{3}-[0-9a-f]{12}$/i
...ensures you have a canonically formatted UUID that is Version 1 through 5 and is the appropriate Variant as per RFC4122.
NOTE: Braces { and } ar...