Sorry for this lack of courtesy. Posting the complete example is indeed a good practice. I'll stick to it. Based on your example I tried the following code to add the boundaries as arguments of the validate subroutine. I cannot figure out how to reference the input value in the -validatecommand. I have tried $_, $_[0] and $xVConsSflEmbMax but none seems to work... 
use strict;
use Tk;

my $xVConsSflEmbMax0 = 1.0;
my $xVConsSflEmbMax = $xVConsSflEmbMax0;

my $mw = new MainWindow();
my $entry = $mw->Entry(
  -textvariable     => \$xVConsSflEmbMax,
  -width            => 3,
  -validate         => 'focusout',
  -validatecommand  => [\&validSub,$_[0],0,1],
  -invalidcommand   => sub {$xVConsSflEmbMax=$xVConsSflEmbMax0},
) -> pack;

MainLoop;

sub validSub {
  my ($val,$min,$max) = @_;
  $val ||= 0;
  $min ||= -1E10;
  $max ||= 1E10;
  if( $val !~ /^\d*\.?\d+$/ ) { return 0 }
  elsif (($val >= $min) and ($val <= $max)) {return 1}
  else { return 0 }
}

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In reply to Re^2: perl/Tk Entry validation by contact@solamen.fr
in thread perl/Tk Entry validation by Anonymous Monk

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