Safe Haskell | None |
---|---|

Language | Haskell98 |

- data Evt a :: * -> * = Evt {}
- type Bam a = a -> SE ()
- type Tick = Evt Unit
- boolToEvt :: BoolSig -> Evt Unit
- evtToBool :: Evt a -> SE BoolSig
- sigToEvt :: Sig -> Evt Unit
- stepper :: Tuple a => a -> Evt a -> SE a
- filterE :: (a -> BoolD) -> Evt a -> Evt a
- filterSE :: (a -> SE BoolD) -> Evt a -> Evt a
- accumSE :: Tuple s => s -> (a -> s -> SE (b, s)) -> Evt a -> Evt b
- accumE :: Tuple s => s -> (a -> s -> (b, s)) -> Evt a -> Evt b
- filterAccumE :: Tuple s => s -> (a -> s -> (BoolD, b, s)) -> Evt a -> Evt b
- filterAccumSE :: Tuple s => s -> (a -> s -> SE (BoolD, b, s)) -> Evt a -> Evt b
- type family Snap a :: *
- snapshot :: (Tuple a, Tuple (Snap a)) => (Snap a -> b -> c) -> a -> Evt b -> Evt c
- snaps :: Sig -> Evt D
- sync :: (Default a, Tuple a) => D -> Evt a -> Evt a
- syncBpm :: (Default a, Tuple a) => D -> Evt a -> Evt a
- metroE :: Sig -> Evt Unit
- impulseE :: D -> Evt Unit
- changedE :: [Sig] -> Evt Unit
- triggerE :: Sig -> Sig -> Sig -> Evt Unit
- loadbang :: Evt Unit
- impulse :: D -> Sig
- devt :: D -> Evt a -> Evt D
- eventList :: [(D, D, a)] -> Evt [(D, D, a)]
- cycleE :: (Tuple a, Arg a) => [a] -> Evt b -> Evt a
- iterateE :: Tuple a => a -> (a -> a) -> Evt b -> Evt a
- repeatE :: Tuple a => a -> Evt b -> Evt a
- appendE :: Tuple a => a -> (a -> a -> a) -> Evt a -> Evt a
- mappendE :: (Monoid a, Tuple a) => Evt a -> Evt a
- partitionE :: (a -> BoolD) -> Evt a -> (Evt a, Evt a)
- takeE :: Int -> Evt a -> Evt a
- dropE :: Int -> Evt a -> Evt a
- takeWhileE :: (a -> BoolD) -> Evt a -> Evt a
- dropWhileE :: (a -> BoolD) -> Evt a -> Evt a
- splitToggle :: Evt D -> (Evt D, Evt D)
- toTog :: Tick -> Evt D
- toTog1 :: Tick -> Evt D
- type Rnds a = [(D, a)]
- oneOf :: (Tuple a, Arg a) => [a] -> Evt b -> Evt a
- freqOf :: (Tuple a, Arg a) => Rnds a -> Evt b -> Evt a
- freqAccum :: (Tuple s, Tuple (b, s), Arg (b, s)) => s -> (a -> s -> Rnds (b, s)) -> Evt a -> Evt b
- randDs :: Evt b -> Evt D
- randList :: Int -> Evt b -> Evt [D]
- randInts :: (D, D) -> Evt b -> Evt D
- randSkip :: D -> Evt a -> Evt a
- randSkipBy :: (a -> D) -> Evt a -> Evt a
- range :: (D, D) -> Evt b -> Evt D
- listAt :: (Tuple a, Arg a) => [a] -> Evt D -> Evt a
- every :: (Tuple a, Arg a) => Int -> [Int] -> Evt a -> Evt a
- masked :: (Tuple a, Arg a) => [D] -> Evt a -> Evt a

# Documentation

data Evt a :: * -> *

A stream of events. We can convert a stream of events to
the procedure with the function `runEvt`

. It waits for events
and invokes the given procedure when the event happens.

# Core functions

evtToBool :: Evt a -> SE BoolSig

Converts an event to boolean signal. It forgets everything about the event values. Signal equals to one when an event happens and zero otherwise.

accumSE :: Tuple s => s -> (a -> s -> SE (b, s)) -> Evt a -> Evt b

Accumulator for events with side effects.

filterAccumE :: Tuple s => s -> (a -> s -> (BoolD, b, s)) -> Evt a -> Evt b

Accumulator with filtering. It can skip the events from the event stream. If the third element of the triple equals to 1 then we should include the event in the resulting stream. If the element equals to 0 we skip the event.

filterAccumSE :: Tuple s => s -> (a -> s -> SE (BoolD, b, s)) -> Evt a -> Evt b

Accumulator for events with side effects and filtering. Event triggers only if the first element in the tripplet is true.

type family Snap a :: *

A snapshot of the signal. It converts a type of the signal to the type of the value in the given moment. Instances:

type instance Snap D = D type instance Snap Str = Str type instance Snap Tab = Tab type instance Snap Sig = D type instance Snap (a, b) = (Snap a, Snap b) type instance Snap (a, b, c) = (Snap a, Snap b, Snap c) type instance Snap (a, b, c, d) = (Snap a, Snap b, Snap c, Snap d) type instance Snap (a, b, c, d, e) = (Snap a, Snap b, Snap c, Snap d, Snap e) type instance Snap (a, b, c, d, e, f) = (Snap a, Snap b, Snap c, Snap d, Snap e, Snap f)

type Snap Sig = D | |

type Snap D = D | |

type Snap Str = Str | |

type Snap Tab = Tab | |

type Snap (a, b) = (Snap a, Snap b) | |

type Snap (a, b, c) = (Snap a, Snap b, Snap c) | |

type Snap (a, b, c, d) = (Snap a, Snap b, Snap c, Snap d) | |

type Snap (a, b, c, d, e) = (Snap a, Snap b, Snap c, Snap d, Snap e) | |

type Snap (a, b, c, d, e, f) = (Snap a, Snap b, Snap c, Snap d, Snap e, Snap f) |

snapshot :: (Tuple a, Tuple (Snap a)) => (Snap a -> b -> c) -> a -> Evt b -> Evt c

Get values of some signal at the given events.

Constructs an event stream that contains values from the given signal. Events happens only when the signal changes.

sync :: (Default a, Tuple a) => D -> Evt a -> Evt a

Executes actions synchronized with global tempo (in Hz).

runEvtSync tempoCps evt proc

syncBpm :: (Default a, Tuple a) => D -> Evt a -> Evt a Source

the sync function but time is measured in beats per minute.

# Opcodes

# Higher-level event functions

devt :: D -> Evt a -> Evt D Source

Constant event stream. It produces the same value (the first argument) all the time.

cycleE :: (Tuple a, Arg a) => [a] -> Evt b -> Evt a Source

Constructs an event stream that contains an infinite repetition values from the given list. When an event happens this function takes the next value from the list, if there is no values left it starts from the beggining of the list.

iterateE :: Tuple a => a -> (a -> a) -> Evt b -> Evt a Source

When something happens on the given event stream resulting event stream contains an application of some unary function to the given initial value. So the event stream contains the values:

[s0, f s0, f (f s0), f (f (f s0)), ...]

repeatE :: Tuple a => a -> Evt b -> Evt a Source

Substitutes all values in the input stream with the given constant value.

appendE :: Tuple a => a -> (a -> a -> a) -> Evt a -> Evt a Source

Accumulates a values from the given event stream with binary function. It's a variant of the fold for event streams.

appendE z f evt

When value `a`

happens with `evt`

, the resulting event stream contains
a value (z `f`

a) and in the next time `z`

equals to this value.

partitionE :: (a -> BoolD) -> Evt a -> (Evt a, Evt a) Source

Splits event stream on two streams with predicate.

takeE :: Int -> Evt a -> Evt a Source

Takes the ns events from the event stream and ignores the rest of the stream.

dropE :: Int -> Evt a -> Evt a Source

Drops the ns events from the event stream and leaves the rest of the stream.

takeWhileE :: (a -> BoolD) -> Evt a -> Evt a Source

Takes events while the predicate is true.

dropWhileE :: (a -> BoolD) -> Evt a -> Evt a Source

Drops events while the predicate is true.

splitToggle :: Evt D -> (Evt D, Evt D) Source

Splits a toggle event stream on on-events and off-events.

toTog1 :: Tick -> Evt D Source

Converts clicks to alternating 1 and 0 (toggle event stream with first value set to 1)

oneOf :: (Tuple a, Arg a) => [a] -> Evt b -> Evt a Source

Constructs an event stream that contains values from the given list which are taken in the random order.

freqOf :: (Tuple a, Arg a) => Rnds a -> Evt b -> Evt a Source

Constructs an event stream that contains values from the given list which are taken in the random order. In the list we specify not only values but the frequencies of occurrence. Sum of the frequencies should be equal to one.

freqAccum :: (Tuple s, Tuple (b, s), Arg (b, s)) => s -> (a -> s -> Rnds (b, s)) -> Evt a -> Evt b Source

This function combines the functions `accumE`

and
`freqOf`

. We transform the values of the event stream
with stateful function that produce not just values but the list of values
with frequencies of occurrence. We apply this function to the current state
and the value and then at random pick one of the values.

randList :: Int -> Evt b -> Evt [D] Source

An event stram of lists of random values in the interval `(0, 1)`

.
The first argument is the length of the each list.

randInts :: (D, D) -> Evt b -> Evt D Source

An event stream of the integers taken from the given diapason.

randSkip :: D -> Evt a -> Evt a Source

Skips elements at random.

randSkip prob

where `prob`

is probability of includinng the element in the output stream.

randSkipBy :: (a -> D) -> Evt a -> Evt a Source

Skips elements at random.

randSkip probFun

It behaves just like `randSkip`

, but probability depends on the value.

listAt :: (Tuple a, Arg a) => [a] -> Evt D -> Evt a Source

Turns an event of indices to the event of the values from the list. A value is taken with index.

every :: (Tuple a, Arg a) => Int -> [Int] -> Evt a -> Evt a Source

Specialization of the function `masked`

.

every n [a, b, c, ..] evt

constructs a mask that skips first `n`

elements and then produces
an event and skips next (a - 1) events, then produces an event and
skips next (b - 1) events and so on. It's useful for construction of
the percussive beats. For example

every 0 [2] (metroE 2)

triggers an event on the odd beats. With this function we can create a complex patterns of cyclic events.