order of operations with conditionals at the end

[BeneSphinx]

I like the natural flow of statements with the conditional at the end, but I'm having some difficulty understanding how it relates to order of operations, since if/unless/etc aren't listed in the Operator Precedence table (http://perldoc.perl.org/perlop.html#Operator-Precedence-and-Associativity) For example code like:

my $message = "Congrats" unless not defined $reward;

or

my @badVals;
for my $val (@vals){
  push @badVals, $val && next if isBad($val);
  print "$val is a good val.\n";
}

I would love to write these without parentheses because it's so nice to read, but I'm concerned about ambiguity. Wondering if you have any tips so I can try to at least get halfway there without danger... overall I'm curious about best practices for these kinds of statements.