Re: Evaluate an operator given as a string

[jwkrahn@xxxxxxx (John W. Krahn)]

Amit Koren wrote:
> Hi all.

Hello,

> I'm trying to pass the operators ">="  or "<="  to a subroutine,
> and then use it inside an "if" statement.
> What changes should i apply to the code below to make it work ?
>
> my_evaluate ( ">=");
>
> sub my_evaluate {
>    my ($sign) = @_;
>    my $x = 10;
>    my $y = 20;
>    if ($x $sign $y) { # want it to be treated as:  if ($x >= $y)
>      ...do something...
>    }
> }

my $greater_than_or_equal_to = sub { $_[0] >= $_[1] )
my $less_than_or_equal_to    = sub { $_[0] <= $_[1] )


my_evaluate( $greater_than_or_equal_to );

sub my_evaluate {
   my ( $sign ) = @_;
   my $x = 10;
   my $y = 20;
   if ( $sign->( $x, $y ) ) { # want it to be treated as:  if ($x >= $y)
     ...do something...
   }
}



John
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