conf

type Configuration interface {
	// AddPath adds a directory path to the file search path. Paths are
	// searched in FIFO order.
	AddPath(path string) *conf

	// Get retrieves a value by name.
	Get(name string) Valuer

	GetDefault(name string) Valuer

	// Name returns the configuration name. For a file-based config this
	// is the filename without the file extension.
	Name() string

	// Parse parses the configuration data.
	Parse() error

	// Path returns the list of file search paths.
	Path() []string

	// Read implements io.Reader
	Read(p []byte) (n int, err error)

	// Set sets a value in this configuration
	Set(name string, value Valuer) *conf

	// Define a default config value.
	SetDefault(name string, value Valuer) *conf

	// Define all default config values.
	SetDefaults(defaults map[string]Valuer) *conf

	// Define a prefix to use when accessing environment variables.
	// Environment variable names are case sensitive. Eg:
	//
	//	conf.SetEnvPrefix("SVC_")
	//	id := conf.Get("ID")
	SetEnvPrefix(prefix string) *conf

	// SetName sets the configuration name. For a file-based config this
	// is the filename without the file extension.
	SetName(name string) *conf

	// SetPath replaces the current file search path. Paths are searched
	// in FIFO order.
	SetPath(path []string) *conf

	// Watch watches configuration sources for changes and automatically
	// updates available values.
	Watch()
}

type ValueList []Valuer

type ValueMap map[string]Valuer

type Valuer interface {
	// Bool returns the boolean representation of the value, or an error if
	// the type conversion is not possible.
	Bool() (bool, error)
	// Float returns the float64 representation of the value, or an error if
	// the type conversion is not possible.
	Float() (float64, error)
	// Float32 returns the float32 representation of the value, or an error
	// if the type conversion is not possible.
	Float32() (float32, error)
	// Float64 returns the float64 representation of the value, or an error
	// if the type conversion is not possible.
	Float64() (float64, error)
	// Int returns the int representation of the value, or an error if the
	// type conversion is not possible.
	Int() (int, error)
	// List returns the ValueList representation of the value, or an error
	// if the type conversion is not possible.
	List() (ValueList, error)
	// Map returns the ValueMap representation of the value, or an error if
	// the type conversion is not possible.
	Map() (ValueMap, error)
	// String returns the boolean representation of the value, or an error
	// if the type conversion is not possible.
	String() (string, error)
}