private function addTransformer(KeyTransformerInterface $keyTransformer)
    {
        $finds = array_filter($this->transformers, function ($transformer) use ($keyTransformer) {
            return (\get_class($transformer) === \get_class($keyTransformer));
        });

        if (\count($finds) < 1) {
            $this->transformers[] = $keyTransformer;
        }
    }
private function addTransformer(KeyTransformerInterface $keyTransformer)
    {
        $finds = array_filter($this->transformers, function ($transformer) use ($keyTransformer) {
            return (\get_class($transformer) === \get_class($keyTransformer));
        });

        if (\count($finds) < 1) {
            $this->transformers[] = $keyTransformer;
        }
    }
private function addTransformer ( KeyTransformerInterface $ keyTransformer ) { $ finds = array_filter ( $ this -> transformers , function ( $ transformer ) use ( $ keyTransformer ) { return ( \ get_class ( $ transformer ) === \ get_class ( $ keyTransformer ) ) ; } ) ; if ( \ count ( $ finds ) < 1 ) { $ this -> transformers [ ] = $ keyTransformer ; } }
Add a key transformer.

Will not add it if one of the same class has already been added.

@param KeyTransformerInterface $keyTransformer
Add a key transformer .