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Why are static variables considered evil?
... variables represent global state. That's hard to reason about and hard to test: if I create a new instance of an object, I can reason about its new state within tests. If I use code which is using static variables, it could be in any state - and anything could be modifying it.
I could go on for qu...
Is there any way to call a function periodically in JavaScript?
...f strings that will be "evaled" to those functions.
// example 1
function test() {
alert('called');
}
var interval = setInterval(test, 10000);
Or:
// example 2
var counter = 0;
var interval = setInterval(function() { alert("#"+counter++); }, 5000);
...
Which timestamp type should I choose in a PostgreSQL database?
... NULL DEFAULT NOW(),
CHECK(EXTRACT(TIMEZONE FROM my_timestamp) = '0')
);
test=> SET timezone = 'America/Los_Angeles';
SET
test=> INSERT INTO my_tbl (my_timestamp) VALUES (NOW());
ERROR: new row for relation "my_tbl" violates check constraint "my_tbl_my_timestamp_check"
test=> SET timezon...
Trim spaces from start and end of string
..., '');
for (var i = str.length - 1; i >= 0; i--) {
if (/\S/.test(str.charAt(i))) {
str = str.substring(0, i + 1);
break;
}
}
return str;
}
"if you want to handle long strings exceptionally fast in all browsers".
References
blog.stevenlevith...
Select first row in each GROUP BY group?
...Example.
If total can be NULL, you most probably want the row with the greatest non-null value. Add NULLS LAST like demonstrated. See:
Sort by column ASC, but NULL values first?
The SELECT list is not constrained by expressions in DISTINCT ON or ORDER BY in any way. (Not needed in the simple case ...
Check if user is using IE
...
/Edge\/|Trident\/|MSIE /.test(window.navigator.userAgent) I know this works on 10 and 11. If you can verify <IE9 and Edge, edit answer.
– Indolering
May 5 '15 at 23:59
...
What is “rvalue reference for *this”?
... parameter" of the function†:
// t.cpp
#include <iostream>
struct test{
void f() &{ std::cout << "lvalue object\n"; }
void f() &&{ std::cout << "rvalue object\n"; }
};
int main(){
test t;
t.f(); // lvalue
test().f(); // rvalue
}
Output:
$ clang++ -std=c++...
How can I compare two lists in python and return matches
...
A quick performance test showing Lutz's solution is the best:
import time
def speed_test(func):
def wrapper(*args, **kwargs):
t1 = time.time()
for x in xrange(5000):
results = func(*args, **kwargs)
t2 = ...
Performance of FOR vs FOREACH in PHP
...look into it a little further; I might edit my original question with more teststo including some of the new 5.3 features. @Col. Shrapnel: FOR is almost universal programing-kindergardn level, FOREACH is simpler syntax. As far as readability they seem to be on equal ground. This is all so low l...
html5 localStorage error with Safari: “QUOTA_EXCEEDED_ERR: DOM Exception 22: An attempt was made to
...to removeItem are ignored.
I believe the simplest fix (although I haven't tested this cross browser yet) would be to alter the function isLocalStorageNameSupported() to test that you can also set some value.
https://github.com/marcuswestin/store.js/issues/42
function isLocalStorageNameSupported()...