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Is it possible to index substr from right to left?

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# 1  
Old 02-26-2013
Is it possible to index substr from right to left?
Hello, all

Suppose I have a string "0123456789", if i want to get the substr "56", I know I can use following method:

Code:
$ string="0123456789"
$ echo ${string:5:2}
56

I am wondering if there is some command like:

Code:
$ echo ${string:6:-2}

which can also get the same output "56"?
# 2  
Old 02-27-2013
Yes:

Code:
$ echo ${string:${#string}-2:2}
89
$ echo ${string:${#string}-5:2}
56

# 3  
Old 02-27-2013
Or simply:
Code:
$ echo ${string: -5:2}
56

This User Gave Thanks to Yoda For This Post:
Chubler_XL
# 4  
Old 02-27-2013
Thank you for reply.

Maybe I did not explain clearly: what I mean "from right to left" is, for example :

Code:
string = "0123456789"

if we want to get "567", we can do by starting from "5", then counting from left to right three digits; we can also do by starting from "7", then counting from right to left three digits.
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