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How do I convert a dictionary to a JSON String in C#?
...tring[] args)
{
Dictionary<int, List<int>> foo = new Dictionary<int, List<int>>();
foo.Add(1, new List<int>( new int[] { 1, 2, 3, 4 }));
foo.Add(2, new List<int>(new int[] { 2, 3, 4, 1 }));
foo.Add(3, new Li...
eval command in Bash and its typical uses
...able substitutions and command substitutions (i.e. anytime there's a $): "$foo", "$(foo)". Always put double quotes around variable and command substitutions, unless you know you need to leave them off. Without the double quotes, the shell performs field splitting (i.e. it splits value of the variab...
Java generics - why is “extends T” allowed but not “implements T”?
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To add to the confusion getFoo(List<? super Foo> fooList) ONLY works with the class that literally are extended by Foo like class Foo extends WildcardClass. In this case a List<WildcardClass> would be acceptable input. However any class...
Is key-value observation (KVO) available in Swift?
...Object subclass. Consider that you wanted to observe the bar property of a Foo class. In Swift 4, specify bar as dynamic property in your NSObject subclass:
class Foo: NSObject {
@objc dynamic var bar = 0
}
You can then register to observe changes to the bar property. In Swift 4 and Swift 3.2...
regex for matching something if it is not preceded by something else
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You want to use negative lookbehind like this:
\w*(?<!foo)bar
Where (?<!x) means "only if it doesn't have "x" before this point".
See Regular Expressions - Lookaround for more information.
Edit: added the \w* to capture the characters before (e.g. "beach").
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Difference between Hive internal tables and external tables?
...r node it uses to keep track of state.
For instance, when you CREATE TABLE FOO(foo string) LOCATION 'hdfs://tmp/';, this table schema is stored in the database.
If you have a partitioned table, the partitions are stored in the database(this allows hive to use lists of partitions without going to th...
How can I tell when a MySQL table was last updated?
In the footer of my page, I would like to add something like "last updated the xx/xx/200x" with this date being the last time a certain mySQL table has been updated.
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Why use def main()? [duplicate]
...
if the content of foo.py
print __name__
if __name__ == '__main__':
print 'XXXX'
A file foo.py can be used in two ways.
imported in another file : import foo
In this case __name__ is foo, the code section does not get execute...
Declare multiple module.exports in Node.js
...
module.js:
const foo = function(<params>) { ... }
const bar = function(<params>) { ... }
//export modules
module.exports = {
foo,
bar
}
main.js:
// import modules
var { foo, bar } = require('module');
// pass your p...
How to pass the value of a variable to the stdin of a command?
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But why? Also, I can't reproduce any problems: foo1=-; foo2='"'; foo3=\!; cat<<<"$foo1"; cat<<<"$foo2"; cat<<<"$foo3" works fine for me. What exactly do the three " do? AFAIK you are just prepending and appending an empty string.
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