Re: Add PostgreSQL home page to --help output

On 2020-02-11 10:34, Daniel Gustafsson wrote:
> Pardon my weak autoconf-skills, what does the inverted brackets (]foo[ as
> opposed to [foo]) do in the below?
> 
> -Please also contact<pgsql-bugs@lists.postgresql.org>  to see about
> +Please also contact <]AC_PACKAGE_BUGREPORT[> to see about

AC_PACKAGE_BUGREPORT is an Autoconf macro, set up by AC_INIT.  The call 
above is in the context of

AC_MSG_ERROR([[ ... text ... ]])

The brackets are quote characters that prevent accidentally expanding a 
token in the text as a macro.  So in order to get AC_PACKAGE_BUGREPORT 
expanded, we need to undo one level of quoting.

See also 
<https://www.gnu.org/savannah-checkouts/gnu/autoconf/manual/autoconf-2.69/html_node/M4-Quotation.html#M4-Quotation> 
for more information.

-- 
Peter Eisentraut              http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services