How about storing it in a subroutine instead?

my $func = sub { my $x = shift; return 3 * ( $x**3 ) - 2 * $x + 4 };

my $to_x = $func->( $x );
my $to_y = $func->( $y );

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eval is a big, dangerous stick to carry around.

In reply to Re: Recover a mathematical expression from a string. by chromatic
in thread Recover a mathematical expression from a string. by misho

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