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Safe integer parsing in Ruby

... test in Ruby 1.9. Integer(:foobar) => can't convert Symbol into Integer (TypeError) – GutenYe Dec 25 '11 at 9:10 ...
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How to determine the Boost version on a system?

... Tested with boost 1.51.0: std::cout << "Using Boost " << BOOST_VERSION / 100000 << "." // major version << BOOST_VERSION / 100 % 1000 << "." // minor version ...
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Why is printing “B” dramatically slower than printing “#”?

...u're invoking all manner of external processing not related to what you're testing the performance of. That's a bug in your measurement procedure, pure and simple. On the other hand, if you view the problem not as measurement, but understanding the discrepancy, then yes, not printing is a debugging...
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How to get element by class name? [duplicate]

...entsByClassName suppose you have some elements and applied a class name 'test', so, you can get elements like as following var tests = document.getElementsByClassName('test'); its returns an instance NodeList, or its superset: HTMLCollection (FF). Read more ...
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In where shall I use isset() and !empty()

... In the most general way : isset tests if a variable (or an element of an array, or a property of an object) exists (and is not null) empty tests if a variable (...) contains some non-empty data. To answer question 1 : $str = ''; var_dump(isset($str)); ...
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What is a lambda (function)?

...an primitive type. Predicate<Integer> pred = x -> x % 2 == 0; // Tests if the parameter is even. boolean result = pred.test(4); // true Lua adder = function(x) return function(y) return x + y end end add5 = adder(5) add5(1) == 6 -- true Kotlin val pred = { x: I...
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How do I prevent commands from showing up in Bash history?

...tory (as well as duplicates). For example: $ HISTCONTROL=ignoreboth $ echo test1 $ echo test2 $ history | tail -n2 1015 echo test1 1016 history | tail -n2 Here is what man bash says: HISTCONTROL A colon-separated list of values controlling how commands are saved on the history list. If the l...
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How do you disable viewport zooming on Mobile Safari?

... got it working in iOS 12 with the following code: if (/iPad|iPhone|iPod/.test(navigator.userAgent)) { window.document.addEventListener('touchmove', e => { if(e.scale !== 1) { e.preventDefault(); } }, {passive: false}); } With the first if statement I ensure it will only exec...
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MySQL: What's the difference between float and double?

... Perhaps this example could explain. CREATE TABLE `test`(`fla` FLOAT,`flb` FLOAT,`dba` DOUBLE(10,2),`dbb` DOUBLE(10,2)); We have a table like this: +-------+-------------+ | Field | Type | +-------+-------------+ | fla | float | | flb | float | | dba ...
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Simulator error FBSSystemServiceDomain code 4

...l broken in Xcode 6.0.1, this workaround still works (thankfully) -- Apple testing FTW. – Adam Oct 11 '14 at 14:10 1 ...