The version of Syndicate current at the conclusion of Tony Garnock-Jones's PhD research, end-of-2017/start-of-2018.
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#lang scribble/manual
@(require (for-label (only-in racket struct #;equal?)
(prefix-in untyped: (for-label syndicate/actor)))
@title{Typed Syndicate}
@defform[(U type ...)]{
The type representing the union of @racket[type ...].
An alias for @racket[(U)].
The type representing any possible assertion, and, in an @racket[AssertionSet],
the possibility for an infinite set of assertions.
The type of @racket[_] patterns.
@defform[(Bind type)]{
The type of @racket[$] patterns.
The type associated with identifiers bound by @racket[start-facet].
@defform[(Role (x) type ...)]{
The type of a facet named @racket[x] and endpoints described by @racket[type
@defform[(Stop X type ...)]{
The type of a @racket[stop] action.
@defform[(Field type)]{
The type of a field containing values of @racket[type].
@defform[(Shares type)]{
The type of an @racket[assert] endpoint.
@defform[#:literals (OnStart OnStop Asserted Retracted)
(Reacts EventDesc type ...)
[(EventDesc (code:line OnStart)
(code:line OnStart)
(code:line (Asserted event-type))
(code:line (Retracted event-type)))]]{
The type of a @racket[on] endpoint that reacts to events described by
@racket[EventDesc] with the behavior given by @racket[type ...].
@defform[(Asserted type)]
@defform[(Retracted type)])]{
See @racket[Reacts].
@defform[(Actor type)]{
The type of an actor that operates in a dataspace with a certain communication
@defform[(ActorWithRole comm-type behavior-type)]{
An @racket[Actor] type with the additional @racket[behavior-type] describing the
actor's behavior in terms of a @racket[Role].
@defform[(Sends type)]{
The type of a @racket[send!] action.
@defform[(Realize type)]{
The type of a @racket[realize!] action.
@deftogether[(@defform[(Branch type ...)]
@defform[(Effs type ...)])]{
Types that may arise in descriptions in @racket[Role] types due to branching and
@defform[(Tuple type ...)]{
The type of @racket[tuple] expressions.
An alias for @racket[(Tuple)].
@defform[(AssertionSet type)]{
The type for a set of assertions of a certain @racket[type]. Note that these are
not interoperable with the general purpose @racket[set] data structures.
@defform[( (X ...) type)]{
Universal quantification over types.
@defform[#:literals (Computation Value Endpoints Roles Spawns)
( type ... (Computation (Value result-type)
(Endpoints ep-type ...)
(Roles role-type ...)
(Spawns spawn-type ...)))]{
The type of a function with parameters @racket[type ...] that returns @racket[result-type]. The type includes the effects of any actions performed by the function:
@item{@racket[Endpoints]: includes any endpoint installation effects, such as from @racket[assert] and @racket[on].}
@item{@racket[Roles]: includes any script action effects, such as from @racket[start-facet], @racket[stop], and @racket[send!].}
@item{@racket[Spawns]: includes descriptions of any @racket[spawn] actions.}
@defform[(→fn type-in ... type-out)]{
Shorthand for a @racket[] type with no effects.
@defform[(proc maybe-quantifiers type-in ... maybe-arrow type-out
[(maybe-quantifiers (code:line)
(code:line #:forall (X ...)))
(maybe-arrow (code:line)
(code:line )
(code:line ->))
(maybe-endpoints (code:line)
(code:line #:endpoints (e ...)))
(maybe-roles (code:line)
(code:line #:roles (r ...)))
(maybe-spawns (code:line)
(code:line #:spawns (s ...)))]]{
A more convenient notation for writing (potentially polymorphic) function types
with effects. Shorthand for @racket[( (X ...) ( type-in ... (Computation
(Value type-out) (Endpoints e ...) (Roles r ...) (Spawns s ...))))].
@deftogether[(@defform[(Computation type ...)]
@defform[(Value type)]
@defform[(Endpoints type)]
@defform[(Roles type)]
@defform[(Spawns type)])]{
See @racket[].
@section{User Defined Types}
@defform[(define-constructor (ctor-id slot-id ...)
maybe-alias ...)
[(maybe-type-ctor (code:line)
(code:line #:type-constructor type-ctor-id))
(maybe-alias (code:line)
(code:line #:with alias alias-body))]]{
Defines a container analagous to a prefab @racket[struct]. Includes accessor
functions for each @racket[slot-id]. (But not, presently, a predicate function).
When a @racket[type-ctor-id] is provided, the type of such structures is
@racket[(type-ctor-id type ...)], where each @racket[type] describes the value
of the corresponding slot. When not provided, the type constructor is named by
appending @racket["/t"] to @racket[ctor-id].
Each @racket[alias] and @racket[alias-body] creates an instance of
@defform[#:literals (:)
(define-constructor* (ctor-id : type-ctor-id slot-id ...)
maybe-alias ...)]{
An abbreviated form of @racket[define-constructor].
@defform[#:literals (:)
(assertion-struct ctor-id : type-ctor-id (slot-id ...))]{
An abbreviated form of @racket[define-constructor].
@defform[#:literals (:)
(message-struct ctor-id : type-ctor-id (slot-id ...))]{
An abbreviated form of @racket[define-constructor].
@section{Actor Forms}
@defform[(run-ground-dataspace type expr ...)]{
Starts a ground, i.e. main, dataspace of the program, with the given
communication @racket[type] and initial actors spawned by @racket[expr ...].
@defform[(spawn maybe-type s)
[(maybe-type (code:line)
(code:line type))]]{
Spawns an actor with behavior given by @racket[s]. The @racket[type] gives the
communication type of the enclosing dataspace. When absent, @racket[type] is
supplied by the nearest lexically enclosing @racket[spawn] or @racket[dataspace]
form, if any exist.
@defform[(dataspace type expr ...)]{
Spawns a dataspace with communication type @racket[type] as a child of the
dataspace enclosing the executing actor. The script @racket[expr ...] spawns the
initial actors of the new dataspace.
@defform[(start-facet id maybe-spec expr ...+)
[(maybe-spec (code:line)
(code:line #:implements type)
(code:line #:includes-behavior type))]]{
Start a facet with name @racket[id] and endpoints installed through the
evaluation of @racket[expr ...].
@defform[(stop id expr ...)]{
Terminate the facet @racket[id] with continuation script @racket[expr ...]. Any
facets started by the continuation script survive the termination of facet
@defform[#:literals (start stop message asserted retracted _ $)
(on event-description body ...+)
[(event-description (code:line start)
(code:line stop)
(code:line (message pattern))
(code:line (asserted pattern))
(code:line (retracted pattern)))
(pattern (code:line _)
(code:line ($ id type))
(code:line ($ id))
(code:line $id)
(code:line $id:type)
(code:line (ctor pattern ...))
(code:line expr))]]{
Creates an event handler endpoint that responds to the event specified by
@racket[event-description]. Executes the @racket[body ...] for each matching
event, with any pattern variables bound to their matched value.
Patterns have the following meanings:
@item{@racket[_] matches anything.}
@item{@racket[($ id type)] matches any value and binds it to @racket[id] with
assumed type @racket[type].}
@item{@racket[($ id)] is like @racket[($ id type)], but attempts to use the
current communication type to fill in the @racket[type] of potential matches.
May raise an error if no suitable communication type is in scope.}
@item{@racket[(? pred pattern)] matches values where @racket[(pred val)] is not
@racket[#f] and that match @racket[pattern].}
@item{@racket[$id:type] is shorthand for @racket[($ id type)].}
@item{@racket[$id] is shorthand for @racket[($ id)].}
@item{@racket[(ctor pat ...)] matches values built by applying the constructor
@racket[ctor] to values matching @racket[pat ...]. @racket[ctor] is usually
a @racket[struct] name.}
@item{@racket[expr] patterns match values that are @racket[equal?] to
@defform[(on-start expr ...+)]{
Shorthand for @racket[(on start expr ...)].
@defform[(on-stop expr ...+)]{
Shorthand for @racket[(on stop expr ...)].
@defform[(assert expr)]{
Creates an assertion endpoint with the value of @racket[expr].
@defform[(know expr)]{
Creates an internal assertion endpoint with the value of @racket[expr].
@defform[(send! expr)]{
Broadcast a dataspace message with the value of @racket[expr].
@defform[(realize! expr)]{
Broadcast an actor-internal message with the value of @racket[expr].
@defform[#:literals (:)
(field [id maybe-type expr] ...)
[(maybe-type (code:line)
(code:line type)
(code:line : type))]]{
Defines fields of type @racket[type] with names @racket[id] and initial values
@racket[expr]. If @racket[type] is not provided, the type of the initial
expression is used as the type of the field.
@defform[(ref id)]{
Reference the @racket[field] named @racket[id].
@defform[(set! id expr)]{
Update the value the @racket[field] named @racket[id].
@defform[(begin/dataflow expr ...+)]{
Evaluate and perform the script @racket[expr ...], and then again each time a
field referenced by the script updates.
@defform[(during pattern expr ...+)]{
Engage in behavior for the duration of a matching assertion. The syntax of
@racket[pattern] is the same as described by @racket[on].
@defform[(during/spawn pattern expr ...+)]{
Like @racket[during], but spawns an actor for the behavior @racket[expr ...].
@defform[(define/query-value name absent-expr pattern expr
[(maybe-on-add (code:line)
(code:line #:on-add on-add-expr))
(maybe-on-remove (code:line)
(code:line #:on-remove on-remove-expr))]]{
Equivalent to the untyped @racket[untyped:define/query-value].
@defform[(define/query-set name pattern expr
[(maybe-on-add (code:line)
(code:line #:on-add on-add-expr))
(maybe-on-remove (code:line)
(code:line #:on-remove on-remove-expr))]]{
Equivalent to the untyped @racket[untyped:define/query-set].
@defform[(define/query-hash name pattern key-expr value-expr
[(maybe-on-add (code:line)
(code:line #:on-add on-add-expr))
(maybe-on-remove (code:line)
(code:line #:on-remove on-remove-expr))]]{
Equivalent to the untyped @racket[untyped:define/query-hash].
@defform[(define/dataflow name maybe-type expr)
[(maybe-type (code:line)
(code:line type))]]{
Define a @racket[field] named @racket[name], whose value is reevaluated to the
result of @racket[expr] each time any referenced field changes. When
@racket[type] is not supplied, the field has the type of the given
@defform[(tuple expr ...)]{
Constructs a tuple of arbitrary arity.
@section{Requiring From Outside Typed Syndicate}
@section{Behavioral Checking}