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Is the Scala 2.8 collections library a case of “the longest suicide note in history”? [closed]
...ith something like map or collect would be built in, and nobody has to see all the hoops the compiler has to go through to make them work smoothly. In Scala, it's all in a library, and therefore out in the open.
In fact the functionality of map that's supported by its complicated type is pretty adv...
Apache Spark: map vs mapPartitions?
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I'm seeing the opposite -- even with very small operations, its faster to call mapPartitions and iterate than call map. I am assuming that this is just the overhead of starting the language engine that will process the map task. (I'm in R, which may have more startup...
Compelling examples of custom C++ allocators?
What are some really good reasons to ditch std::allocator in favor of a custom solution? Have you run across any situations where it was absolutely necessary for correctness, performance, scalability, etc? Any really clever examples?
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PostgreSQL create table if not exists
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CREATE TABLE myschema.mytable (i integer);
END IF;
END
$func$;
Call:
SELECT create_mytable(); -- call as many times as you want.
Notes:
The columns schemaname and tablename in pg_tables are case-sensitive. If you double-quote identifiers in the CREATE TABLE statement, you need ...
Why are regular expressions so controversial? [closed]
...ions. And not just slow, but the performance of the regex engine can be totally unpredictable when faced with arbitrary (user-supplied) inputs.
– Pacerier
Dec 1 '15 at 21:53
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AngularJS sorting by property
...'s rows in the filter e.g. for(var objectKey in input) { input[objectKey]['_key'] = objectKey; array.push(input[objectKey]); } Like that we can use <div ng-repeat="value in object | orderObjectBy:'order'" ng-init="key = value['_key']">
– Nicolas Janel
Jul...
Boost Statechart vs. Meta State Machine
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As there seems to be much interest, please allow me to give my (obviously biased) opinion, which should therefore be taken with a grain of salt:
MSM is much faster
MSM requires no RTTI or anything virtual
MSM has a more complete UML2 support (for example internal tr...
Equation (expression) parser with precedence?
...ursively, for example, using your sample string,
1+11*5
to do this manually, you would have to read the 1, then see the plus and start a whole new recursive parse "session" starting with 11... and make sure to parse the 11 * 5 into its own factor, yielding a parse tree with 1 + (11 * 5).
This a...
Java SE 6 vs. JRE 1.6 vs. JDK 1.6 - What do these mean?
I see many different Java terms floating around. I need to install the JDK 1.6. It was my understanding that Java 6 == Java 1.6. However, when I install Java SE 6, I get a JVM that reports as version 11.0! Who can solve the madness?
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Trigger a button click with JavaScript on the Enter key in a text box
... This worked for me due to fact that the inline method, instead of calling function with similar code in it, allows you to return false on the call and avoid postback. In my case the "click" method invokes a __doPostback async call and without the "return false;" would just reload the page.
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