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C++ equivalent of java's instanceof
...
Try using:
if(NewType* v = dynamic_cast<NewType*>(old)) {
// old was safely casted to NewType
v->doSomething();
}
This requires your compiler to have rtti support enabled.
EDIT:
I've had some good comments on this answer!
Every time you nee...
Mapping over values in a python dictionary
...ch function; the easiest way to do this is to use a dict comprehension:
my_dictionary = {k: f(v) for k, v in my_dictionary.items()}
In python 2.7, use the .iteritems() method instead of .items() to save memory. The dict comprehension syntax wasn't introduced until python 2.7.
Note that there is ...
How to download image using requests
...flate). You can force it to decompress for you anyway by setting the decode_content attribute to True (requests sets it to False to control decoding itself). You can then use shutil.copyfileobj() to have Python stream the data to a file object:
import requests
import shutil
r = requests.get(settin...
How to query SOLR for empty fields?
...ou need to change QueryParameter.cs (Create a new parameter)
private bool _negativeQuery = false;
public QueryParameter(string field, string value, ParameterJoin parameterJoin = ParameterJoin.AND, bool negativeQuery = false)
{
this._field = field;
this._value = value.Trim();
this._para...
Convert hyphens to camel case (camelCase)
...and have it included in your project.
var str = 'my-hyphen-string';
str = _.camelCase(str);
// results in 'myHyphenString'
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How to do what head, tail, more, less, sed do in Powershell? [closed]
...txt | more # or less if you have it installed
gc log.txt | %{ $_ -replace '\d+', '($0)' } # sed
This works well enough for small files, larger ones (more than a few MiB) are probably a bit slow.
The PowerShell Community Extensions include some cmdlets for specialised file stuf...
Coding Practices which enable the compiler/optimizer to make a faster program
...ovide an example of loop unrolling
Before:
unsigned int sum = 0;
for (size_t i; i < BYTES_TO_CHECKSUM; ++i)
{
sum += *buffer++;
}
After unrolling:
unsigned int sum = 0;
size_t i = 0;
**const size_t STATEMENTS_PER_LOOP = 8;**
for (i = 0; i < BYTES_TO_CHECKSUM; **i = i / STATEMENTS_PER_L...
convert a JavaScript string variable to decimal/money
...onesomeday
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Dealing with float precision in Javascript [duplicate]
...000000004
> (x * cf) * (y * cf) / (cf * cf)
0.02
Quick solution:
var _cf = (function() {
function _shift(x) {
var parts = x.toString().split('.');
return (parts.length < 2) ? 1 : Math.pow(10, parts[1].length);
}
return function() {
return Array.prototype.reduce.call(argum...
Execute the setInterval function without delay the first time
...interval with immediate execution
var myInterval = setIntervalImmediately( _ => {
console.log('hello');
}, 1000);
// clear interval after 4.5 seconds
setTimeout( _ => {
clearInterval(myInterval);
}, 4500);
To be cheeky, if you really need to use setInterval then you ...