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Getting the name of a child class in the parent class (static context)
...ution I have found.
Tested with PHP 7+
Use the function get_class()link
<?php
abstract class bar {
public function __construct()
{
var_dump(get_class($this));
var_dump(get_class());
}
}
class foo extends bar {
}
new foo;
?>
The above example will output:
stri...
Using mixins vs components for code reuse in Facebook React
... key)
});
},
validate: function () {
var errors = _.filter(_.keys(this.validators), function (key) {
var validator = this.validators[key],
value = this.state[key];
return !validator(value);
}, this);
this.setState({
'errors': err...
Check string for palindrome
... increment (++i1 and --i2), we can also use post increment (i1++, i2--)result is same i think !
– user0946076422
Aug 15 '15 at 3:44
...
How do I check if a string contains another string in Swift?
...o Swift"
if string.range(of:"Swift") != nil {
print("exists")
}
// alternative: not case sensitive
if string.lowercased().range(of:"swift") != nil {
print("exists")
}
Older Swift
var string = "hello Swift"
if string.rangeOfString("Swift") != nil{
println("exists")
}
// alternati...
How to sum a variable by group
...y x
1 First 30
2 Second 5
3 Third 34
In the example above, multiple dimensions can be specified in the list. Multiple aggregated metrics of the same data type can be incorporated via cbind:
aggregate(cbind(x$Frequency, x$Metric2, x$Metric3) ...
(embedding @thelatemail comment), ag...
enum - getting value of enum on string conversion
... return str(self.value)
... x = 1
... y = 2
...
>>> D.x
<D.x: 1>
>>> print(D.x)
1
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ADB Android Device Unauthorized
...o longer authorized on ADB for whatever reason.
1. Check if authorized:
<ANDROID_SDK_HOME>\platform-tools>adb devices
List of devices attached
4df798d76f98cf6d unauthorized
2. Revoke USB Debugging on phone
If the device is shown as unauthorized, go to the developer options on th...
How to make an element width: 100% minus padding?
...
Padding a wrapping div also produces non-identical results to adding padding to the input directly.
– Felix Fung
Jun 5 '12 at 0:27
...
C++ Double Address Operator? (&&)
... The operator returns a pointer to the new vector.
This way,
std::vector<int> a(100, 10);
std::vector<int> b = a;
for(unsigned int i = 0; i < b.size(); i++)
{
std::cout << b[i] << ' ';
}
Even though we gave vector a values, vector b has the values. It's the magic o...
How to avoid warning when introducing NAs by coercion
...
Although this is the preferred response, the answer by jangorecki below seems, to me, more solid.
– Ian
Jul 6 at 15:29
...