Re: Unable to dereference function-local nameref to global variable of same name

[Piotr Grzybowski]

Hi,

 amending the previous approach; please find the attached patch: the global 
namerefs are followed, and resolved in the function scope. It works as follows:

bash-4.4$ typeset -n v=w; typeset -n w=x; typeset -n x=v; x=4
bash: warning: x: circular name reference.

bash-4.4$ declare -n ref="HOME"; declare -n ref2=ref; f() { declare -n 
ref2="$1"; echo $ref2; }; f ref2;
bash: declare: warning: ref2: circular name reference
bash: warning: ref2: circular name reference
/Users/merlin

bash-4.4$ function bug { typeset -n var="$1"; printf "%s\n" "$var"; }; 
var="hello"; bug var;
bash: typeset: warning: var: circular name reference
bash: warning: var: circular name reference
hello

 I have no idea what it breaks, I know it does not break the tests, and tries 
to address the reported issue. Please review.

cheers,
pg

find_variable_nameref_follows_global_nameref_patch.diff
Description: Binary data

On 10 Aug 2016, at 18:06, Andreas Kusalananda Kähäri wrote:

> Configuration Information [Automatically generated, do not change]:
> Machine: x86_64
> OS: openbsd6.0
> Compiler: cc
> Compilation CFLAGS:  -DPROGRAM='bash' -DCONF_HOSTTYPE='x86_64' 
> -DCONF_OSTYPE='openbsd6.0' -DCONF_MACHTYPE='x86_64-unknown-openbsd6.0' 
> -DCONF_VENDOR='unknown' -DLOCALEDIR='/usr/local/share/locale' 
> -DPACKAGE='bash' -DSHELL  -DHAVE_CONFIG_H   -I.  -I. -I./include -I./lib  
> -DUSE_MKTEMP -DUSE_MKSTEMP -I/usr/local/include -O2 -pipe
> uname output: OpenBSD uerfale 6.0 GENERIC.MP#38 amd64
> Machine Type: x86_64-unknown-openbsd6.0
> 
> Bash Version: 4.3
> Patch Level: 46
> Release Status: release
> 
> Description:
>    When declaring a variable in a function as a nameref, it can not
>    be dereferenced if the variable it's a nameref to happen to have
>    the same name as the nameref itself.  This imposes unnecessary
>    restrictions on the caller.
> 
>    Also seen in GNU bash, version 4.3.39(1)-release (x86_64-apple-darwin15).
> 
> Repeat-By:
>    function bug {
>        typeset -n var="$1"
>        printf "%s\n" "$var"
>    }
> 
>    var="hello"
>    bug var
> 
>    Result:
>    bash: warning: var: circular name reference
> 
>    Expected result: The string "hello" outputted with a terminating
>    newline (as with ksh93).
>