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What's the point of having pointers in Go?
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I really like example taken from http://www.golang-book.com/8
func zero(x int) {
x = 0
}
func main() {
x := 5
zero(x)
fmt.Println(x) // x is still 5
}
as contrasted with
func zero(xPtr *int) {
*xPtr = 0
}
func main() {
x := 5
zero(&x)
fmt.Printl...
mongoDB/mongoose: unique if not null
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As of MongoDB v1.8+ you can get the desired behavior of ensuring unique values but allowing multiple docs without the field by setting the sparse option to true when defining the index. As in:
email : {type: String, trim: true, index: true,...
Error :Request header field Content-Type is not allowed by Access-Control-Allow-Headers
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answered Sep 13 '12 at 19:58
Mark JonesMark Jones
11.7k22 gold badges4545 silver badges6161 bronze badges
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New Line on PHP CLI
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248
Use double quotes ".
echo "next line\n";
Additional you can use the system-dependent constant...
Will writeToFile:atomically: overwrite data?
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answered Jan 17 '17 at 20:28
IgorIgor
10.5k44 gold badges4646 silver badges6666 bronze badges
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Build the full path filename in Python
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edited Aug 28 at 23:23
answered Aug 20 '11 at 16:49
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Where are my postgres *.conf files?
I have recently reinstalled postgresql 8.3 on my Ubuntu 8.04 after update. Used EnterpriseDB package. I can connect to the database locally, I see system DB postgres but I can't configure it because I can't find config files. Searched through entire hard drive and found only samples like pg_hba.con...
how to set a value for a span using JQuery
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cletuscletus
561k152152 gold badges873873 silver badges927927 bronze badges
3
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Java 8 stream's .min() and .max(): why does this compile?
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The answer is in the way that the new lambda functionality works in Java 8. It relies on a concept which is informally known as "single abstract method" interfaces, or "SAM" interfaces. The idea is that any interface with one abstract method can be automatically implemented by any lambda - or me...
List of special characters for SQL LIKE clause
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For SQL Server, from http://msdn.microsoft.com/en-us/library/ms179859.aspx :
% Any string of zero or more characters.
WHERE title LIKE '%computer%' finds all book titles with the word 'computer' anywhere in the book title.
_ Any single character.
WHERE au_fname LIKE '_ean' finds all fou...