Documentation

A class that can generate unique numbers

Create a TH expression that returns the a formatted string containing the name of the module curLoc is spliced into, and the line where it was spliced.

Cache the result of a monadic action

Cache the result of a monadic action using a UniqMap

Cache the result of a monadic action using a OMap

Same as indexNote with last two arguments swapped

Unsafe indexing, return a custom error message when indexing fails

x y -> floor (logBase x y), x > 1 && y > 0

x y -> ceiling (logBase x y), x > 1 && y > 0

Get the package id of the type of a value >>> pkgIdFromTypeable (undefined :: TopEntity) "clash-prelude-0.99.3-64904d90747cb49e17166bbc86fec8678918e4ead3847193a395b258e680373c"

Left-biased choice on maybes

Left-biased choice on maybes

Right-to-left composition of Kleisli arrows. (>=>), with the arguments flipped.

Note how this operator resembles function composition (.):

(.)   ::            (b ->   c) -> (a ->   b) -> a ->   c
(<=<) :: Monad m => (b -> m c) -> (a -> m b) -> a -> m c

Left-to-right composition of Kleisli arrows.

'(bs >=> cs) a' can be understood as the do expression

do b <- bs a
   cs b

Fanout: send the input to both argument arrows and combine their output.

The default definition may be overridden with a more efficient version if desired.

A mirror image of first.

The default definition may be overridden with a more efficient version if desired.

Send the first component of the input through the argument arrow, and copy the rest unchanged to the output.

Split the input between the two argument arrows and combine their output. Note that this is in general not a functor.

The default definition may be overridden with a more efficient version if desired.

on b u x y runs the binary function b on the results of applying unary function u to two arguments x and y. From the opposite perspective, it transforms two inputs and combines the outputs.

((+) `on` f) x y = f x + f y

Typical usage: sortBy (compare `on` fst).

Algebraic properties:

• (*) `on` id = (*) -- (if (*) ∉ {⊥, const ⊥})

• ((*) `on` f) `on` g = (*) `on` (f . g)

• flip on f . flip on g = flip on (g . f)

Build lenses (and traversals) with a sensible default configuration.

e.g.

data FooBar
  = Foo { _x, _y :: Int }
  | Bar { _x :: Int }
makeLenses ''FooBar

will create

x :: Lens' FooBar Int
x f (Foo a b) = (\a' -> Foo a' b) <$> f a
x f (Bar a)   = Bar <$> f a
y :: Traversal' FooBar Int
y f (Foo a b) = (\b' -> Foo a  b') <$> f b
y _ c@(Bar _) = pure c

makeLenses = makeLensesWith lensRules

Source Span

A SrcSpan identifies either a specific portion of a text file or a human-readable description of a location.

Built-in "bad" SrcSpans for common sources of location uncertainty

Request a CallStack.

NOTE: The implicit parameter ?callStack :: CallStack is an implementation detail and should not be considered part of the CallStack API, we may decide to change the implementation in the future.

Since: base-4.9.0.0