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.