Re: Problem with pattern replacing when STRING is an expandable char

[Mike Stroyan]

>
> Repeat-By:
>     a=111.1
>     echo ${a//[0-9]/x}
>
>     correctly gives "xxx.x", but
>
>     echo ${a//[0-9]/*}
>
>     gives a listing of files in current directory. Seems that the "*"
>     is expanded before replacing the pattern.
>
>     It workes the right way at least up to bash-3.1.17(1)-release
>
>     But if you set
>
>     a=111
>
>     it doesn't even work in 3.1.17 right.

  The pathname expansion of "*" is not done until after the parameter
expansion substitution.  That is the documented behavior.  The following
example shows that echo of the "***.*" pattern matches files and
directories that have a "." in their name.  Setting a to "111" results
in a pathname pattern of "***" that matches all of the files.
Double quoting the substitution prevents pathname expansion.

$ echo $BASH_VERSION
3.2.25(1)-release
$ touch a b c.d e.f
$ ls
a  b  c.d  e.f
$ a=111.1
$ echo ${a//[0-9]/*}
c.d e.f
$ echo "${a//[0-9]/*}"
***.*
$ a=111
$ echo ${a//[0-9]/*}
a b c.d e.f
$ echo "${a//[0-9]/*}"
***
$ 

-- 
Mike Stroyan <mike@stroyan.net>