find_package(Foo REQUIRED)

[Alexander Neundorf]

On Wednesday 17 June 2009, Allen Winter wrote:
> On Tuesday 16 June 2009 5:36:14 pm Alexander Neundorf wrote:
> > On Tuesday 16 June 2009, Allen Winter wrote:
> > > Howdy,
> > >
> > > Maybe this should be a feature of cmake itself.. but I wish for
> > > find_package(Foo REQUIRED) to print a nicer message
> > > if Foo is not found.
> > >
> > > We have the macro_log_feature() stuff for the optional packages
> > > which creates the nice summary at the end of the cmake run,
> > > but when required FOO is not found all we get is a terse error and
> > > quit.
> > >
> > > I wonder.. can we overload find_package() with a COMMENT option?
> > > i.e.
> > > find_package(Foo REQUIRED COMMENT "Foo is a critical library and this
> > > software cannot be build without it. Please install Foo
> > > <http://www.foo.org> version 2.9 or higher")
> > >
> > > and have the COMMENT printed on termination?
> > >
> > > Or maybe there is already something like this and I'm not seeing it?
> >
> > The second argument to find_package_handle_standard_args() can be
> > either "DEFAULT_MSG", then the default message is printed, or it can be a
> > custom message. I think this should be good enough ?
> > But until now nobody inserted custom messages there.
>
> Not quite good enough because most of the REQUIRED FindFoo.cmake's
> are not ours -- they belong to CMake itself.

Also there improved messages can be committed.
> > > find_package(Foo REQUIRED COMMENT "Foo is a critical library and this
> > > software cannot be build without it. Please install Foo
> > > <http://www.foo.org> version 2.9 or higher")

The first sentence is quite generic, having a modified default error message 
should be no problem. Can you send a patch for 
FindPackageHandleStandardArgs.cmake ?
The second sentence is still relatively generic with some additional 
information. Let's see.

Alex