src/Router/Routes/RouteBinding.php
protected function bindPartConcat($var, ServerRequestInterface $request, array $parts, &$part)
    {
        if (!is_string($var) || $var[0] !== '~' || substr($var, -1) !== '~') {
            return false;
        }
        
        $pieces = array_map('trim', explode('~', substr($var, 1, -1)));
        $bound = array_filter($this->bind($pieces, $request, $parts));
        $part = [join('', $bound)];
        
        return true;
    }
protected function bindPartConcat($var, ServerRequestInterface $request, array $parts, &$part)
    {
        if (!is_string($var) || $var[0] !== '~' || substr($var, -1) !== '~') {
            return false;
        }
        
        $pieces = array_map('trim', explode('~', substr($var, 1, -1)));
        $bound = array_filter($this->bind($pieces, $request, $parts));
        $part = [join('', $bound)];
        
        return true;
    }
protected function bindPartConcat ( $ var , ServerRequestInterface $ request , array $ parts , & $ part ) { if ( ! is_string ( $ var ) || $ var [ 0 ] !== '~' || substr ( $ var , - 1 ) !== '~' ) { return false ; } $ pieces = array_map ( 'trim' , explode ( '~' , substr ( $ var , 1 , - 1 ) ) ) ; $ bound = array_filter ( $ this -> bind ( $ pieces , $ request , $ parts ) ) ; $ part = [ join ( '' , $ bound ) ] ; return true ; }
Bind part if it's an concatenation

@param mixed                  $var
@param ServerRequestInterface $request
@param array                  $parts
@param array                  $part     OUTPUT
@return boolean
Bind part if it s an concatenation