Try concatenating the vars for use in the substitution:

use strict;
use warnings;

my $lhs = '(\d*?)-(.*?)-(.*)';
my $rhs = '$1.$2.$3';

while ( my $var = <DATA> ) {
    chomp $var;
    $var =~ s/$lhs/$rhs/ee;
    print $var, "\n";
}

__DATA__
123-456-789
-456-789
789

[download]

Output:

123456789
456789
789

[download]

From the error message, it appears that the results of the first evaluation is ambiguous to the interpreter when it attempts to evaluate it without the concatenation operator.

In reply to Re: "ee" in Regular Expression: version issue? by Kenosis
in thread "ee" in Regular Expression: version issue? by Anonymous Monk

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