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Why doesn't .NET/C# optimize for tail-call recursion?
...n was responsible for the machine code.
The CLR itself does support tail call optimization, but the language-specific compiler must know how to generate the relevant opcode and the JIT must be willing to respect it.
F#'s fsc will generate the relevant opcodes (though for a simple recursion it may j...
Query to count the number of tables I have in MySQL
... Just a note about the use databasename; command. If the database is really big, the command can execute with a long wait time. In that case, login should be done with the option -A, ie: mysql -uroot -p -A, and the command will work fast.
– azurecorn
Jul 21...
Difference between break and continue statement
...necessary to exit a loop before the loop has finished fully iterating over all the step values. For example, looping over a list of numbers until you find a number that satisfies a certain condition. Or looping over a stream of characters from a file until a certain character is read.
In the follow...
Why doesn't Dijkstra's algorithm work for negative weight edges?
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Recall that in Dijkstra's algorithm, once a vertex is marked as "closed" (and out of the open set) - the algorithm found the shortest path to it, and will never have to develop this node again - it assumes the path developed to ...
Differences between Emacs and Vim
...and weeks till you will be happy with it and then you will learn new stuff all the time. You will be annoyed when you don't have access to it and constantly change your config. You won't be able to use other peoples emacs versions easily and it won't just be installed. It uses Lisp, which is great. ...
How to detect escape key press with pure JS or jQuery?
...cated as of jQuery 3.0... you should use .off
– freefaller
Apr 24 '18 at 14:07
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What is the difference between '>' and a space in CSS selectors?
...o scenarios div > span { } vs. div span { }
Here, the (space) selects all the all the <span> elements inside <div> element even if they are nested inside more than one element. The > selects all the children of <div> element but if they are not inside another element.
Take...
Django-DB-Migrations: cannot ALTER TABLE because it has pending trigger events
...son for this maybe because you try to set a column to NOT NULL when it actually already has NULL values.
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Hiding user input on terminal in Linux script
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Just supply -s to your read call like so:
$ read -s PASSWORD
$ echo $PASSWORD
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In Ruby, is there an Array method that combines 'select' and 'map'?
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I usually use map and compact together along with my selection criteria as a postfix if. compact gets rid of the nils.
jruby-1.5.0 > [1,1,1,2,3,4].map{|n| n*3 if n==1}
=> [3, 3, 3, nil, nil, nil]
jruby-1.5.0 > [1...