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In absence of preprocessor macros, is there a way to define practical scheme specific flags at proje

... The simplest example is the DEBUG=1 macro that is defined by default for all Xcode projects in the default scheme for the Run build. One could query #ifdef DEBUG ... and make decisions in the code accordingly, even compiling out non-necessary code. ...
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Passing multiple error classes to ruby's rescue clause in a DRY fashion

...ne it in some other class, you have to refer to it with its namespace. Actually, it does not have to be a constant. Splat Operator The splat operator * "unpacks" an array in its position so that rescue *EXCEPTIONS means the same as rescue FooException, BarException You can also use it withi...
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Which timestamp type should I choose in a PostgreSQL database?

...ative TIMESTAMPs. From a programmatic and consistency perspective, ensure all calculations are made using UTC as the time zone. This isn’t a PostgreSQL requirement, but it helps when integrating with other programming languages or environments. Setting a CHECK on the column to make sure the writ...
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Python - write() versus writelines() and concatenated strings

... More specifically, writelines expects an iterable. You can use a list, a tuple, or a generator. – Mark Ransom Sep 11 '12 at 20:52 ...
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What's the difference between an exclusive lock and a shared lock?

... When the students are reading (shared locks) what is on the board: They all can read what is on it, together => Multiple shared locks can co-exist. The teacher waits for them to finish reading before she clears the board to write more => If one or more shared locks already exist, exclusive ...
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What are the differences between virtual memory and physical memory?

...e (in case of other implementations of virtual memory, we maybe shouldn't call it the "page table"). The page table is in physical memory as well - often in kernel-reserved spaces that user programs cannot write over. Virtual memory is typically larger than physical memory - there wouldn't be much ...
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ab load testing

...While ab runs, there will be -c clients hitting the site. This is what actually decides the amount of stress your site will suffer during the benchmark. -n: Indicates how many requests are going to be made. This just decides the length of the benchmark. A high -n value with a -c value that your ser...
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Why doesn't Dictionary have AddRange?

...doesn't have any meaning to an associative container, as the range of data allows for duplicate entries. E.g if you had an IEnumerable<KeyValuePair<K,T>> that collection does not guard against duplicate entries. The behavior of adding a collection of key-value pairs, or even merging tw...
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Why is Class.newInstance() “evil”?

... This is the very nature of reflection in general ... not at all specific to Constructor.newInstance(). – Ryan Delucchi Oct 24 '08 at 23:35 29 ...
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JavaScript click event listener on class

... This works perfectly. Thank you. I actually didn't realise that jQuery did the looping. Great help Anudeep. Here's your working answer: jsfiddle.net/LWda3/2 – 30secondstosam Oct 29 '13 at 10:33 ...