Re: How does {x..y} supposed to work?

[Reuti]

Am 13.05.2021 um 18:32 schrieb Lawrence Velázquez:

> On Thu, May 13, 2021, at 12:02 PM, Peng Yu wrote:
>> According to the manpage, x and y can be single characters. "the
>> expression expands to each character lexicographically between x and
>> y, inclusive".
>> 
>> So my understanding of the behavior of {x..y} should be that `echo
>> {%..a}` print all the ascii letters between "%" and "a" including "%"
>> and "a", but it doesn't do so. Do I interpret the manual incorrectly?
>> Or the bash implementation does not match the manpage completely?
> 
> The code explicitly wants alphabetics.

The output:

bash-5.1$ echo {Z..a}
Z [  ] ^ _ ` a

seems to fall out of the "valid" range then?

-- Reuti


>  The manual could probably
> stand to be a little more specific than just "characters".
> 
> https://git.savannah.gnu.org/cgit/bash.git/tree/braces.c?id=ce23728#n497
> 
>  /* Now figure out whether LHS and RHS are integers or letters.  Both
>     sides have to match. */
>  lhs_t = (legal_number (lhs, &tl)) ? ST_INT :
>               ((ISALPHA (lhs[0]) && lhs[1] == 0) ?  ST_CHAR : ST_BAD);
> 
> 
> -- 
> vq
>