Music.Theory.DB.Common

Type

type Entry k v = (k, v)

type Record k v = [Entry k v]

type DB k v = [Record k v]

type Key = String

type Value = String

type Entry' = Entry Key Value

type Record' = Record Key Value

type DB' = DB Key Value

Record

record_key_seq :: Record k v -> [k]

The sequence of keys at Record.

record_has_key :: Eq k => k -> Record k v -> Bool

True if Key is present in Entity.

record_key_histogram :: Ord k => Record k v -> [(k, Int)]

histogram of record_key_seq.

record_has_duplicate_keys :: Ord k => Record k v -> Bool

Duplicate keys predicate.

record_lookup_by :: (k -> k -> Bool) -> k -> Record k v -> [v]

Find all associations for key using given equality function.

record_lookup :: Eq k => k -> Record k v -> [v]

record_lookup_by of ==.

record_lookup_at :: Eq k => (k, Int) -> Record k v -> Maybe v

nth element of record_lookup.

record_lookup_uniq :: Eq k => k -> Record k v -> Maybe v

Variant of record_lookup requiring a unique key. Nothing indicates there is no entry, it is an error if duplicate keys are present.

record_has_key_uniq :: Eq k => k -> Record k v -> Bool

True if key exists and is unique.

record_lookup_uniq_err :: Eq k => k -> Record k v -> v

Error variant.

record_lookup_uniq_def :: Eq k => v -> k -> Record k v -> v

Default value variant.

record_delete_by :: (k -> k -> Bool) -> k -> Record k v -> Record k v

Remove all associations for key using given equality function.

record_delete :: Eq k => k -> Record k v -> Record k v

record_delete_by of ==.

DB

db_key_set :: Ord k => DB k v -> [k]

Preserves order of occurence.

db_lookup_by :: (k -> k -> Bool) -> (v -> v -> Bool) -> k -> v -> DB k v -> [Record k v]

db_lookup :: (Eq k, Eq v) => k -> v -> DB k v -> [Record k v]

db_has_duplicate_keys :: Ord k => DB k v -> Bool

db_key_histogram :: Ord k => DB k v -> [(k, Int)]

db_to_table :: Ord k => (Maybe v -> e) -> DB k v -> ([k], [[e]])

Collating duplicate keys.

record_collate' :: Eq k => (k, [v]) -> Record k v -> Record k [v]

record_collate :: Eq k => Record k v -> Record k [v]

Collate adjacent entries of existing sequence with equal key.

record_uncollate :: Record k [v] -> Record k v