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How to check whether a file or directory exists?
...iven file or directory exists
func exists(path string) (bool, error) {
_, err := os.Stat(path)
if err == nil { return true, nil }
if os.IsNotExist(err) { return false, nil }
return false, err
}
Edited to add error handling.
...
What is the Java equivalent of PHP var_dump?
PHP has a var_dump() function which outputs the internal contents of an object, showing an object's type and content.
11 An...
Looking to understand the iOS UIViewController lifecycle
...nd viewDidLayoutSubviews go on this flowchart?
– Max_Power89
Dec 18 '14 at 16:40
7
This diagram ...
What is the difference between String.Empty and “” (empty string)?
...private hidebysig instance string foo() cil managed
{
.maxstack 8
L_0000: ldstr "foo"
L_0005: ret
}
.method private hidebysig instance string bar() cil managed
{
.maxstack 8
L_0000: ldstr "bar"
L_0005: ldsfld string [mscorlib]System.String::Empty
L_000a: call string [msc...
How do you install Boost on MacOS?
...st.org/users/download/#live
Unpack and go into the directory:tar -xzf boost_1_50_0.tar.gz
cd boost_1_50_0
Configure (and build bjam):
./bootstrap.sh --prefix=/some/dir/you/would/like/to/prefix
Build:
./b2
Install:./b2 install
Depending on the prefix you choose in Step 3, you might need to sudo S...
Unix - create path of folders and file
...or the code example can be: mkdir -p /my/other/path/here && touch $_/cpredthing.txt. The $_ expands to essentially the "last argument in the last command executed".
– Sgnl
Apr 19 '16 at 1:37
...
What is a “callback” in C and how are they implemented?
...y're implemented using function pointers. Here's an example:
void populate_array(int *array, size_t arraySize, int (*getNextValue)(void))
{
for (size_t i=0; i<arraySize; i++)
array[i] = getNextValue();
}
int getNextRandomValue(void)
{
return rand();
}
int main(void)
{
int m...
Why does the MongoDB Java driver use a random number generator in a conditional?
... laws it is a trivial observation that this piece of code amounts to
if (!_ok && Math.random() <= 0.1)
return res;
The commit that originally introduced this logic had
if (_ok == true) {
_logger.log( Level.WARNING , "Server seen down: " + _addr, e );
} else if (Math.random() < 0...
How well is Unicode supported in C++11?
... what std::string and its siblings should do:
The class template basic_string describes objects that can store a sequence consisting of a varying number of arbitrary char-like objects with the first element of the sequence at position zero.
Well, std::string does that just fine. Does that pro...
Modular multiplicative inverse function in Python
...
If you happen to be using sympy, then x, _, g = sympy.numbers.igcdex(a, m) does the trick.
– Lynn
Sep 16 '16 at 18:15
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