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Last active August 29, 2015 14:12
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A question I had about slice indexing
<gerep> andlabs, the element 0 is "g", 1 is "o", etc. When I do [1:4] it will return "g" as the element at position one because it counts the slice starting from zero. If I'm expecting the count to start from 0, the element at position 4 would be "n" and not "a"
<gerep> andlabs, and this way, for 4 to be "a", the slice count has to start from 1: position 1 = "g", 2 = "o", etc
<andlabs> the element at position 4 starting at 0 is n
<gerep> andlabs, yes!
<andlabs> ut that 4 is the first element /after the end of the slice/
<andlabs> so you get everything from 1 /up to but not including/ 4
<gerep> andlabs, yes, and why not use [1:3] ?
<gerep> andlabs, because the 1 is included but the 4 is not
<andlabs> because this type of coordinate specification is easier to reason about
<andlabs> how many elements are in the slice? 4-1=3
<andlabs> if it was [1:3] then you'd have to say 3-1+1=3
<andlabs> it also means you can say [1:len(x)] to include everything after the first element
<andlabs> and not [1:len(x) - 1]
<andlabs> what if len(x) is 0?
package main
import "fmt"
func main() {
s := [6]string{"G","O","L","A","N","G"}
fmt.Println(s[1:4]) // [O L A]
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