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Is pass-by-value a reasonable default in C++11?
...by value into functions and methods is slow for large objects, and is generally frowned upon. Instead, C++ programmers tend to pass references around, which is faster, but which introduces all sorts of complicated questions around ownership and especially around memory management (in the event that ...
Storing money in a decimal column - what precision and scale?
...
If you are looking for a one-size-fits-all, I'd suggest DECIMAL(19, 4) is a popular choice (a quick Google bears this out). I think this originates from the old VBA/Access/Jet Currency data type, being the first fixed point decimal type in the language; Decimal on...
time.sleep — sleeps thread or process?
...look in Modules/timemodule.c in the Python source, you'll see that in the call to floatsleep(), the substantive part of the sleep operation is wrapped in a Py_BEGIN_ALLOW_THREADS and Py_END_ALLOW_THREADS block, allowing other threads to continue to execute while the current one sleeps. You can also...
Change URL parameters
...Val;
return baseURL + "?" + newAdditionalURL + rows_txt;
}
Function Calls:
var newURL = updateURLParameter(window.location.href, 'locId', 'newLoc');
newURL = updateURLParameter(newURL, 'resId', 'newResId');
window.history.replaceState('', '', updateURLParameter(window.location.href, "param",...
Memcache(d) vs. Varnish for speeding up 3 tier web architecture
...ache will provide info for pages that have a mixture of known and new data allowing you to generate pages faster.
An example that could apply to stackoverflow.com: adding this comment invalidated the page cache, so this page would have to be cleared from Varnish (and also my profile page, which pr...
How do I detect the Python version at runtime? [duplicate]
...
@iBug is correct. The documentation specifically says to instead use sys.version_info for our purpose here. docs.python.org/3/library/sys.html#sys.version
– Max Barraclough
Jan 1 at 19:06
...
Regular Expression to reformat a US phone number in Javascript
... ' + match[2] + '-' + match[3]
}
return null
}
Here's a version that allows the optional +1 international code:
function formatPhoneNumber(phoneNumberString) {
var cleaned = ('' + phoneNumberString).replace(/\D/g, '')
var match = cleaned.match(/^(1|)?(\d{3})(\d{3})(\d{4})$/)
if (match) ...
mysqldump - Export structure only without autoincrement
.../g' > <filename>.sql
(this only works if you have GUI Tools installed: mysqldump --skip-auto-increment)
New UPDATE thanks to comments.
The \b is useless and sometimes will break the command. See this SO topic for explanations.
So the optimized answer would be :
mysqldump -u root -p -h ...
Fundamental difference between Hashing and Encryption algorithms
...tions
They provide a mapping between an arbitrary length input, and a (usually) fixed length (or smaller length) output. It can be anything from a simple crc32, to a full blown cryptographic hash function such as MD5 or SHA1/2/256/512. The point is that there's a one-way mapping going on. It's a...
How best to determine if an argument is not sent to the JavaScript function
...noid (see comments).
Using the || operator has become standard practice - all the cool kids do it - but be careful: The default value will be triggered if the argument evaluates to false, which means it might actually be undefined, null, false, 0, '' (or anything else for which Boolean(...) returns...