You can search for identifiers within the package.
in-package search v0.2.0
type storage
val of_public_key : public key -> storage
val to_public_key : storage -> public key
val of_secret_key : secret key -> storage
val to_secret_key : storage -> secret key
val of_channel_key : channel key -> storage
val to_channel_key : storage -> channel key
val of_nonce : nonce -> storage
val to_nonce : storage -> nonce
val box : secret key -> public key -> storage -> nonce -> storage
val box_open : secret key -> public key -> storage -> nonce -> storage
val fast_box : channel key -> storage -> nonce -> storage
val fast_box_open : channel key -> storage -> nonce -> storage