Two more options for you, depending on how much external info you need to make use of:

somefunction() if $some_condition;

sub somefunction {
    &some_stuff();
    return if $condition;
    &some_more_stuff();
}
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Or, the one that I'll probably get flamed for:

if ($some_condition){
   &some_stuff();
   goto EXIT if $condition;
   &some_more_stuff();
}
EXIT: {};
[download]