module-build-general

Re: [Module::Build] ask() and you will receive

[Randy W. S. <ml...@th...>]

David Wheeler wrote:
> On Apr 8, 2006, at 03:32, Randy W. Sims wrote:
> 
>> my $answer;
>> $answer = Prompter->ask(
>>     prompt  => "What is your favorite programming language?\n",
>>     options => [qw(Perl Ruby Lua Python C C++)],
>>     default => 'unknown',
>>     show_options => 1,
>>     show_default => 0,
>> );
>>
>> print "Answer: $answer\n";
> 
> 
> This actually looks similar to a method I wrote in my subclass. I  think 
> that you might find my "environ" and "callback" options useful  additions:

Thanks! There are some usefull ideas here. I'll probably keep things 
simple for the 0.28 release, but I definately see things like tieing it 
into the new options in the next release.

Might possibly go ahead and add the callback; this very much echos the 
options interface. It has a multi-option type, and callbacks via the 
on_validate handler. OTOH, the user could do this via.

my $need_answer = 1;
while ($need_answer) {
   my $ans = $mb->ask(...);
   $need_answer = !valid_answer( $ans );
}

So a handler only adds a little bit of sugar...

Randy.

Re: [Module::Build] ask() and you will receive

[David W. <da...@ki...>]

On Apr 10, 2006, at 01:25, Randy W. Sims wrote:

> Thanks! There are some usefull ideas here. I'll probably keep  
> things simple for the 0.28 release, but I definately see things  
> like tieing it into the new options in the next release.

I found the environ option very useful for, e.g., PostgreSQL settings.

> Might possibly go ahead and add the callback; this very much echos  
> the options interface. It has a multi-option type, and callbacks  
> via the on_validate handler. OTOH, the user could do this via.
>
> my $need_answer = 1;
> while ($need_answer) {
>   my $ans = $mb->ask(...);
>   $need_answer = !valid_answer( $ans );
> }
>
> So a handler only adds a little bit of sugar...

Yes, but it's cleaner to use a callback, at least from the user's  
point of view.

Best,

David

Re: [Module::Build] ask() and you will receive

[Randy W. S. <ml...@th...>]

David Wheeler wrote:

> =item callback
> 
> A code reference that validates a value input by a user. The value to  
> be checked will be passed in as the first argument and will also be  
> stored in C<$_>. For example, if you wanted to ensure that a value  was 
> an integer, you might pass a code reference like C<sub { /^\d+$/ } >. 
> Note that if the callback sets C<$_> to a different value, the  revised 
> value is the one that will be returned. This can be useful  for parsing 
> one value from another.

Does the callback get called on every value the user enters? Regardless 
of whether it is an open ended query or a multiple choice selection?

Does it get called on values entered as command line options? or 
environment variables?

Using Text::Abbrev to accept short unique abbreviations for answers, do 
we validate before or after expansion?

Randy.

Re: [Module::Build] ask() and you will receive

[David W. <da...@ki...>]

On Apr 14, 2006, at 01:07, Randy W. Sims wrote:

> Does the callback get called on every value the user enters? =20
> Regardless of whether it is an open ended query or a multiple =20
> choice selection?

Yes. Gotta make sure that whatever they type in is valid.

> Does it get called on values entered as command line options? or =20
> environment variables?

Let's see=85yes, it gets called on command-line options and environment =20=

variables. Anywhere that the user is putting in the option, you gotta =20=

check it. Only defaults are ignored.

> Using Text::Abbrev to accept short unique abbreviations for =20
> answers, do we validate before or after expansion?

I would do it after, but if there's an error, include the abbreviated =20=

version in the error message.

Best,

David=