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What are free monads?
I've seen the term Free Monad pop up every now and then for some time, but everyone just seems to use/discuss them without giving an explanation of what they are. So: what are free monads? (I'd say I'm familiar with monads and the Haskell basics, but have only a very rough knowledge of cat...
How to effectively work with multiple files in Vim
I've started using Vim to develop Perl scripts and am starting to find it very powerful.
28 Answers
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What is the difference between `let` and `var` in swift?
What is the difference between let and var in Apple's Swift language?
30 Answers
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Extracting bits with a single multiplication
I saw an interesting technique used in an answer to another question , and would like to understand it a little better.
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Why is the Java main method static?
...ntire class - sometimes you have an instance that hasn't been initialized, and you have to check for it in every method that could be called.
There are just too many edge cases and ambiguities for it to make sense for the JVM to have to instantiate a class before the entry point is called. That's ...
What does “Could not find or load main class” mean?
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The java <class-name> command syntax
First of all, you need to understand the correct way to launch a program using the java (or javaw) command.
The normal syntax1 is this:
java [ <options> ] <class-name> [<arg> ...]
where &...
When is SQLiteOpenHelper onCreate() / onUpgrade() run?
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SQLiteOpenHelper onCreate() and onUpgrade() callbacks are invoked when the database is actually opened, for example by a call to getWritableDatabase(). The database is not opened when the database helper object itself is created.
SQLiteOpenHelper versi...
Practical uses of git reset --soft?
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git reset is all about moving HEAD, and generally the branch ref.
Question: what about the working tree and index?
When employed with --soft, moves HEAD, most often updating the branch ref, and only the HEAD.
This differ from commit --amend as:
it doesn't cre...
What are the -Xms and -Xmx parameters when starting JVM?
Please explain the use of Xms and Xmx parameters in JVMs. What are the default values for them?
5 Answers
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What are the advantages of using a schema-free database like MongoDB compared to a relational databa
I'm used to using relational databases like MySQL or PostgreSQL, and combined with MVC frameworks such as Symfony, RoR or Django, and I think it works great.
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