src/Northern/Common/Util/ArrayUtil.php
public static function insert(&$arr, $path, $value, $delimiter = '.')
    {
        if (! static::exists($arr, $path, $delimiter)) {
            static::set($arr, $path, $value, $delimiter);
        }
    }
public static function insert(&$arr, $path, $value, $delimiter = '.')
    {
        if (! static::exists($arr, $path, $delimiter)) {
            static::set($arr, $path, $value, $delimiter);
        }
    }
public static function insert ( & $ arr , $ path , $ value , $ delimiter = '.' ) { if ( ! static :: exists ( $ arr , $ path , $ delimiter ) ) { static :: set ( $ arr , $ path , $ value , $ delimiter ) ; } }
Inserts a new value into a key or path only if the key or path does not yet
exists.

@param array  $arr
@param string $path
@param mixed  $value
@param string $delimiter
Inserts a new value into a key or path only if the key or path does not yet exists .