dbix::dbstag::constraint(3pm) [debian man page]

DBIx::DBStag::Constraint(3pm)				User Contributed Perl Documentation			     DBIx::DBStag::Constraint(3pm)

NAME

       DBIx::DBStag::Constraint - recursive structure for representing query constraints

SYNOPSIS

DESCRIPTION

       A constraint is a recursive structure for representing query constraints;

	 AND ---  x=1
	   
	    ---- OR   ---  y>2
		   
		    -----  boolfunc(z)

       A constraint is either a bool (AND, OR, NOT) with >0 children, or it can be a leaf node representing an atomic constraint

       the constraint corresponds to a SQLTemplate option block; eg

	 [ name LIKE &name& ]
	 [ name => &name& ]
	 [ start > &min_start& ]
	 [ start => &start& ]
	 [ somefunc(&x&) ]
	 [ somefunc(&x&, &y&) ]
	 [ somefunc(t.col, &x&, &y&) => &z& ]

       the constraint consists of an operator (represented by => in the option block). If no => is present, then it is a simple variable binding.

       A constraint can consist of multiple variable bindings

WEBSITE

       <http://stag.sourceforge.net>

AUTHOR

       Chris Mungall <cjm@fruitfly.org>

COPYRIGHT

       Copyright (c) 2003 Chris Mungall

       This module is free software.  You may distribute this module under the same terms as perl itself

perl v5.12.4							    2011-10-14					     DBIx::DBStag::Constraint(3pm)

HTML::Widget::Constraint::CallbackOnce(3pm)		User Contributed Perl Documentation	       HTML::Widget::Constraint::CallbackOnce(3pm)

NAME

       HTML::Widget::Constraint::CallbackOnce - CallbackOnce Constraint

SYNOPSIS

	   my $c = $widget->constraint( 'CallbackOnce', 'foo', 'bar' )->callback(
	     sub {
	       my ($foo, $bar) = @_;
	       return 1 if $foo == $bar * 2;
	   });

DESCRIPTION

       A callback constraint which will only be run once for each call of "process" in HTML::Widget.

METHODS

   callback
   cb
       Arguments: &callback

       Requires a subroutine reference used for validation, which will be passed a list of values corresponding to the constraint names.

       "cb" is provided as an alias to "callback".

   process
       Overrides "process" in HTML::Widget::Constraint to ensure "validate" is only called once for each call of "validate".

   render_errors
       Arguments: @names

       A list of element names for which an error should be displayed.

       If this is not set, the default behaviour is for the error to be displayed for all of the Constraint's named elements.

   validate
       perform the actual validation.

AUTHOR

       Carl Franks "cfranks@cpan.org"

LICENSE

       This library is free software, you can redistribute it and/or modify it under the same terms as Perl itself.

perl v5.10.1							    2007-03-01			       HTML::Widget::Constraint::CallbackOnce(3pm)