(

(library "alterto.yql")
(import alterto_module '"alterto.yql")

(let config (DataSource 'config))

(let targetType (TupleType (DataType 'Uint8) (DataType 'Utf8)))
(let failValue '((Uint8 '0) (Utf8 '"not converted")))

# (Int32, String) -> (Uint8, Utf8)
(let value '((Int32 '1) (String 'one)))
(let world (Apply (bind alterto_module 'doAlterTo) world value targetType failValue))

# (Int32, String) -> (Uint8, Utf8) (fail)
(let value '((Int32 '1) (String '"garbage\xff")))
(let world (Apply (bind alterto_module 'doAlterTo) world value targetType failValue))

(return world)

)