Re: Problem with sequences with variables?

[Chet Ramey]

On 4/28/21 7:02 PM, Tom (AST) Watson via Bug reports for the GNU Bourne 
Again SHell wrote:
> Hi...
>
> I was trying to do some sequences, and it looks like they don't like variables. 
>  See the following:

Brace expansion happens first, before any of the other word expansions, so
it requires integer constants or alphabetic literals.

> [user@box3 ~]$ echo $BASH_VERSION
> 5.0.17(1)-release
> [user@box3 ~]$ echo {1..10}
> 1 2 3 4 5 6 7 8 9 10
> [user@box3 ~]$ echo $l
> 10
> [user@box3 ~]$ echo {1..${l}}
> {1..10}
> [user@box3 ~]$
>
> Shouldn't the second sequence echo be the same as the first sequence echo?  It 
> would be MUCH more useful if it were.

Maybe, but it's never worked that way and was never intended to. You can
get what you need using eval:

eval echo \{1..${i}}

--
``The lyf so short, the craft so long to lerne.'' - Chaucer
                 ``Ars longa, vita brevis'' - Hippocrates
Chet Ramey, UTech, CWRU    chet@case.edu    http://tiswww.cwru.edu/~chet/