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foldMapOf :: Getting r s a -> (a -> r) -> s -> r

lens	Control.Lens.Combinators

Map each part of a structure viewed through a Lens, Getter, Fold or Traversal to a monoid and combine the results.

>>> foldMapOf (folded . both . _Just) Sum [(Just 21, Just 21)]
Sum {getSum = 42}

foldMap = foldMapOf folded

foldMapOf ≡ views
ifoldMapOf l = foldMapOf l . Indexed

foldMapOf ::                Getter s a      -> (a -> r) -> s -> r
foldMapOf :: Monoid r    => Fold s a        -> (a -> r) -> s -> r
foldMapOf :: Semigroup r => Fold1 s a       -> (a -> r) -> s -> r
foldMapOf ::                Lens' s a       -> (a -> r) -> s -> r
foldMapOf ::                Iso' s a        -> (a -> r) -> s -> r
foldMapOf :: Monoid r    => Traversal' s a  -> (a -> r) -> s -> r
foldMapOf :: Semigroup r => Traversal1' s a -> (a -> r) -> s -> r
foldMapOf :: Monoid r    => Prism' s a      -> (a -> r) -> s -> r

foldMapOf :: Getting r s a -> (a -> r) -> s -> r

iconcatMap :: FoldableWithIndex i f => (i -> a -> [b]) -> f a -> [b]

lens Control.Lens.Combinators

Concatenate the results of a function of the elements of an indexed container with access to the index. When you don't need access to the index then concatMap is more flexible in what it accepts.
```
concatMap ≡ iconcatMap . const
iconcatMap ≡ ifoldMap
```

iconcatMapOf :: IndexedGetting i [r] s a -> (i -> a -> [r]) -> s -> [r]

lens	Control.Lens.Combinators

Concatenate the results of a function of the elements of an IndexedFold or IndexedTraversal with access to the index. When you don't need access to the index then concatMapOf is more flexible in what it accepts.

concatMapOf l ≡ iconcatMapOf l . const
iconcatMapOf ≡ ifoldMapOf

iconcatMapOf :: IndexedGetter i s a     -> (i -> a -> [r]) -> s -> [r]
iconcatMapOf :: IndexedFold i s a       -> (i -> a -> [r]) -> s -> [r]
iconcatMapOf :: IndexedLens' i s a      -> (i -> a -> [r]) -> s -> [r]
iconcatMapOf :: IndexedTraversal' i s a -> (i -> a -> [r]) -> s -> [r]

ifoldMap :: (FoldableWithIndex i f, Monoid m) => (i -> a -> m) -> f a -> m

lens Control.Lens.Combinators

Fold a container by mapping value to an arbitrary Monoid with access to the index i. When you don't need access to the index then foldMap is more flexible in what it accepts.
```
foldMap ≡ ifoldMap . const
```
ifoldMap' :: (FoldableWithIndex i f, Monoid m) => (i -> a -> m) -> f a -> m

lens Control.Lens.Combinators

A variant of ifoldMap that is strict in the accumulator. When you don't need access to the index then foldMap' is more flexible in what it accepts.
```
foldMap' ≡ ifoldMap' . const
```
ifoldMapBy :: FoldableWithIndex i t => (r -> r -> r) -> r -> (i -> a -> r) -> t a -> r

lens Control.Lens.Combinators

No documentation available.
ifoldMapByOf :: IndexedFold i t a -> (r -> r -> r) -> r -> (i -> a -> r) -> t -> r

lens Control.Lens.Combinators

No documentation available.

ifoldMapOf :: IndexedGetting i m s a -> (i -> a -> m) -> s -> m

lens	Control.Lens.Combinators

Fold an IndexedFold or IndexedTraversal by mapping indices and values to an arbitrary Monoid with access to the i. When you don't need access to the index then foldMapOf is more flexible in what it accepts.

foldMapOf l ≡ ifoldMapOf l . const

ifoldMapOf ::             IndexedGetter i s a     -> (i -> a -> m) -> s -> m
ifoldMapOf :: Monoid m => IndexedFold i s a       -> (i -> a -> m) -> s -> m
ifoldMapOf ::             IndexedLens' i s a      -> (i -> a -> m) -> s -> m
ifoldMapOf :: Monoid m => IndexedTraversal' i s a -> (i -> a -> m) -> s -> m

imap :: FunctorWithIndex i f => (i -> a -> b) -> f a -> f b

lens Control.Lens.Combinators

Map with access to the index.
imapAccumL :: TraversableWithIndex i t => (i -> s -> a -> (s, b)) -> s -> t a -> (s, t b)

lens Control.Lens.Combinators

Generalizes mapAccumL to add access to the index. imapAccumL accumulates state from left to right.
```
mapAccumL ≡ imapAccumL . const
```

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