src/Codec/DecodingList.php
public function unless(bool $test, $decodings): self
    {
        return $this->when(true !== $test, $decodings);
    }
public function unless(bool $test, $decodings): self
    {
        return $this->when(true !== $test, $decodings);
    }
Push decodings if the truth test does not evaluate to true.

@param bool $test
@param $decodings
@return DecodingList