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sub increment {
    my ( $number, $incval )  =  @_;
...
while ( my $result  =  $action->() ) {
    print "$result\n";
}

sub do_something {
    my $action  =  shift( @_ );
...
while ( my $result  =  $action->() ) { # <-- The error happens here
    print "$result\n";
}