lib/Elastica/Query/Prefix.php
public function setPrefix(string $key, $value, float $boost = 1.0): self
    {
        return $this->setRawPrefix([$key => ['value' => $value, 'boost' => $boost]]);
    }
public function setPrefix(string $key, $value, float $boost = 1.0): self
    {
        return $this->setRawPrefix([$key => ['value' => $value, 'boost' => $boost]]);
    }
public function setPrefix ( string $ key , $ value , float $ boost = 1.0 ) : self { return $ this -> setRawPrefix ( [ $ key => [ 'value' => $ value , 'boost' => $ boost ] ] ) ; }
Adds a prefix to the prefix query.

@param string       $key   Key to query
@param string|array $value Values(s) for the query. Boost can be set with array
@param float        $boost OPTIONAL Boost value (default = 1.0)

@return $this
Adds a prefix to the prefix query .