src/Composer/Composer.php
public static function installed( $directory, $package ) {
		$command = 'composer show ' . $package . ' -D';

		try {
			App::execute( $command, $directory );
		} catch ( ProcessFailedException $e ) {
			return false;
		}

		return true;
	}
public static function installed( $directory, $package ) {
		$command = 'composer show ' . $package . ' -D';

		try {
			App::execute( $command, $directory );
		} catch ( ProcessFailedException $e ) {
			return false;
		}

		return true;
	}
public static function installed ( $ directory , $ package ) { $ command = 'composer show ' . $ package . ' -D' ; try { App :: execute ( $ command , $ directory ) ; } catch ( ProcessFailedException $ e ) { return false ; } return true ; }
Check if a package is already installed

@param  string  $directory
@param  string  $package
@return boolean
Check if a package is already installed