void push(string $key, mixed $value) Push a value onto an array configuration

bool has(string $key) Determine if the given configuration value exists

Illuminate\Config Classes

array getNamespaces() Returns all registered namespaces with the config

array cascadePackage(string $environment, string $package, string $group, array $items)

bool offsetExists(string $key) Determine if the given configuration option

void prepend(string $key, mixed $value) Prepend a value onto an array configuration

bool exists(string $group, string $namespace = null) Determine if the given

void set(array|string $key, mixed $value = null) Set a given configuration

Filesystem getFilesystem()