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| Description |
This module provides records of signals and signal-related data.
A record has a type of the following form:
(X :& name_1 ::: signal_1 `Of` val_1 :& ... :& name_n ::: signal_n `Of` val_n) style
A value of such a type is a list of fields where the ith field has type (name_i :::
signal_i `Of` val_i) style.
(:::) is a data family. Its style parameter is a phantom type which selects the instance
of the family. For a concrete style type, the type (name ::: signal `Of`
val) style covers name-value pairs where the type of the values depends on signal and
val. For example, if style is of the form SignalStyle era, the values have type
signal era val. This leads to records of signals with identical era. With the styles
Connector Consumer and Connector Producer, it is possible to form records of
consumers and producers.
Field names are represented by types which are declared as follows:
data Name = Name
This makes it possible to use names as types (allowing the use of names in compile-time checks)
but also as expressions and patterns.
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| Synopsis |
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| Records
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| class Record record where | Source |
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The class of all record types.
A record type is a type of records without the style parameter. Therefore, it has kind * ->
*.
| | | Methods | | build :: thing X -> (forall record name signal val. Record record => thing record -> thing (record :& (name ::: (signal `Of` val)))) -> thing record | Source |
| A general method for building record-related “things”.
For each record type, this method constructs a value which is somehow related to this
record type. Such a value is called a thing. The type parameter thing maps record
types to the types of their corresponding things. The first argument of build gives
the thing of the empty record type while the second argument tells how to transform a
thing of an arbitrary record type into the thing of this record type extended
with an arbitrary field type.
build is used, for example, to implement the function cat.
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| |  Instances | |
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| The type of empty records.
| | Constructors | | | Instances | |
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| data (record :& field) style | Source |
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| The type of non-empty records, consisting of an initial record and a last field.
| | Constructors | | !(record style) :& !(field style) | |
| | Instances | | Record record => Record (record :& (name ::: Of signal val)) | | OptRecord optRecord => OptRecord (optRecord :& (Opt name ::: Of signal val)) | | OptRecord optRecord => OptRecord (optRecord :& (Req name ::: Of signal val)) | | (Dissection record remainder subname subsignal subval, Subrecord subrecord remainder) => Subrecord (subrecord :& (subname ::: Of subsignal subval)) record | | (TypeEq name lookupName namesAreEq, NameMatchDep namesAreEq record name signal val remainder lookupName lookupSignal lookupVal) => Dissection (record :& (name ::: Of signal val)) remainder lookupName lookupSignal lookupVal |
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| data family (name ::: signalOfVal) style :: * | Source |
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The family of record fields.
Each instance of it matches arbitrary name parameters and all signalOfVal parameters
which are of the form signal `Of` val. The actual choice of the instance
depends only on the style parameter. The structure of fields of a specific style is
documented together with the respective style type.
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| Catenation
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| type family Cat record1 record2 :: * -> * | Source |
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| The catenation of two record types.
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| cat :: (Record record1, Record record2) => record1 style -> record2 style -> Cat record1 record2 style | Source |
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| The catenation of two records.
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| Subrecords
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The class of all pairs of record types where the first is a subrecord of the second.
Currenty, the subrecord relation is only defined for records which do not have multiple
occurences of the same name. A records is a subrecord of another record if all field types
of the first record are also field types of the second, independently of order.
The instance declarations of Subrecord use several helper classes which are hidden. One of
them is the class Presence. You get the error message that no instance of Presence
name could be found if the alleged subrecord contains a name which is not present in the
alleged superrecord.
| | | Methods | | narrow :: record style -> subrecord style | Source |
| | Converts a record into a subrecord by dropping and reordering fields appropriately.
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| | | Instances | |
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| Signal records
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| Records which contain signals of a common era as values.
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The style of signal records of a specific era.
Fields of signal style records have the form name ::= signal.
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| Connector records
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| Records which contain signal consumers as values.
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| Records which contain signal producers as values.
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| Records which which contain signal connectors (producers or consumers) as values.
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| data ConnectorStyle connector | Source |
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The consumer and producer record styles.
ConnectorStyle Consumer is the style of consumer records and ConnectorStyle Producer
is the style of producer records. Fields of connector style records have the form name
::~ connector.
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| Converts a record of consumers into a circuit that consumes a corresponding record of
signals.
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| Converts a record of producers into a circuit that produces a corresponding record of
signals.
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| Produced by Haddock version 2.4.2 |
