$flipt = new \Flipt\Client('https://my-flipt.io', '<apiToken>', '<default namespace>', [ 'default' => 'context' ]);

// test on a boolean flag
$resp = $flipt->boolean('my-boolean');

if ($resp->getEnabled()) {
    // do somthing 
}

// test on variant flag
$resp = $flipt->variant('my-variant');
if ($resp->getVariantKey() == 'demo') {
    // do something
}

// get a variant attachment
$array = $resp->getVariantAttachment();

// the returned value is an array and you can access properties like:
if ($array['key'] == 'demo') {
    // do something
}

$flipt = new \Flipt\Client('https://my-flipt.io', 'token', 'namespace', [ 'environment' => 'test', 'user' => '23' ]);

// will send the context [ 'environment' => 'test', 'user' => '23' ] as defined in the client
$test = $flipt->boolean('flag'); 

// will send the context [ 'environment' => 'test', 'user' => '50' ] as it will merge the client context with the current from the call
$test2 = $flipt->boolean('flag', [ 'user' => '50' ]);

// this client will query against the 'test' namespace
$fliptTest = new \Flipt\Client('https://my-flipt.io', 'token', 'test');

// this will create a new client with all the settings from $fliptTest client except the namespace will changed to 'production'
$fliptProd = $fliptTest->withNamespace('production'),

// this will use namespace 'production'
$fliptProd->boolean('flag')