I am parsing a string and would like to make conditional decisions based on data the stings contains. Could you guys tell me how effective this code is in doing that and if there is a better way I would certainly appreciate knowing that too.

I want to keep the code as easy to read and maintain as possible too. 
if(!defined($mystring)){
    dosumpton("nogames",undef,undef,undef);
} elsif ($mystring){
    ($major,$minor,$bld,$rev) = split(/\./, $mystring);
    if($major){
        if($minor){
            if($bld){
                if($rev){
                    dosumpton($major,$minor,$bld,$rev);
                } else {
                dosumpton($major,$minor,$bld,undef);
                }
            } else {
                dosumpton($major,$minor,undef,undef);
            }
        } else {
            dosumpton($major,undef,undef,undef);
        }
    }
} else {
    # Something went wrong and we should be notified about it
}

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In reply to Are there corner cases I am missing by monk2b

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