Re: suggested warning about perl nested named subroutines

Patch applied.  Thanks.

---------------------------------------------------------------------------


Andrew Dunstan wrote:
>
> I propose to add the following to the plperl docs, following recent
> problems.
>
> comments?
>
> cheers
>
> andrew
>
>
> Index: plperl.sgml
> ===================================================================
> RCS file: /cvsroot/pgsql/doc/src/sgml/plperl.sgml,v
> retrieving revision 2.45
> diff -c -r2.45 plperl.sgml
> *** plperl.sgml 24 Aug 2005 19:16:49 -0000      2.45
> --- plperl.sgml 12 Oct 2005 00:36:33 -0000
> ***************
> *** 53,64 ****
>       # PL/Perl function body
>   $$ LANGUAGE plperl;
>   </programlisting>
> !    The body of the function is ordinary Perl code. A PL/Perl function must
>      always return a scalar value.  You can return more complex structures
>      (arrays, records, and sets) by returning a reference, as discussed
> below.
>      Never return a list.
>     </para>
>
>      <para>
>       The syntax of the <command>CREATE FUNCTION</command> command requires
>       the function body to be written as a string constant.  It is usually
> --- 53,76 ----
>       # PL/Perl function body
>   $$ LANGUAGE plperl;
>   </programlisting>
> !    The body of the function is ordinary Perl code. In fact, the PL/Perl
> !    glue code wraps it inside a Perl subroutine. A PL/Perl function must
>      always return a scalar value.  You can return more complex structures
>      (arrays, records, and sets) by returning a reference, as discussed
> below.
>      Never return a list.
>     </para>
>
> +    <note>
> +       <para>
> +        The use of named nested subroutines is dangerous in Perl,
> especially if
> +        they refer to lexical variables in the enclosing scope. Because
> a PL/Perl
> +        function is wrapped in a subroutine, any named subroutine you
> create will
> +        be nested. In general, it is far safer to create anonymous
> subroutines
> +        which you call via a coderef. See the <literal>perldiag</literal>
> +        man page for more details.
> +       </para>
> +    </note>
> +
>      <para>
>       The syntax of the <command>CREATE FUNCTION</command> command requires
>       the function body to be written as a string constant.  It is usually
>
>
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