function ensureInstalled($formula, $options = [], $taps = [])
    {
        if (! $this->installed($formula)) {
            $this->installOrFail($formula, $options, $taps);
        }
    }
function ensureInstalled($formula, $options = [], $taps = [])
    {
        if (! $this->installed($formula)) {
            $this->installOrFail($formula, $options, $taps);
        }
    }
function ensureInstalled ( $ formula , $ options = [ ] , $ taps = [ ] ) { if ( ! $ this -> installed ( $ formula ) ) { $ this -> installOrFail ( $ formula , $ options , $ taps ) ; } }
Ensure that the given formula is installed.

@param  string  $formula
@param  array  $options
@param  array  $taps
@return void
Ensure that the given formula is installed .