Usage
Blang sexp syntax
type 'a t = private
| True |
| False |
| And of 'a t * 'a t |
| Or of 'a t * 'a t |
| Not of 'a t |
| If of 'a t * 'a t * 'a t |
| Base of 'a |
Note that the sexps are not directly inferred from the type below -- there are lots of fancy shortcuts. Also, the sexps for 'a
must not look anything like blang sexps. Otherwise t_of_sexp
will fail.
include Bin_prot.Binable.S1 with type 'a t := 'a t
val bin_shape_t : Bin_prot.Shape.t -> Bin_prot.Shape.t
val bin_size_t : ('a, 'a t) Bin_prot.Size.sizer1
val bin_write_t : ('a, 'a t) Bin_prot.Write.writer1
val bin_read_t : ('a, 'a t) Bin_prot.Read.reader1
val __bin_read_t__ : ('a, int -> 'a t) Bin_prot.Read.reader1
val bin_writer_t : ('a, 'a t) Bin_prot.Type_class.S1.writer
val bin_reader_t : ('a, 'a t) Bin_prot.Type_class.S1.reader
val bin_t : ('a, 'a t) Bin_prot.Type_class.S1.t
val compare : ('a -> 'a -> Base.Int.t) -> 'a t -> 'a t -> Base.Int.t
val hash_fold_t : (Base.Hash.state -> 'a -> Base.Hash.state) -> Base.Hash.state -> 'a t -> Base.Hash.state
include Ppx_sexp_conv_lib.Sexpable.S1 with type 'a t := 'a t
val t_of_sexp : (Sexplib0.Sexp.t -> 'a) -> Sexplib0.Sexp.t -> 'a t
val sexp_of_t : ('a -> Sexplib0.Sexp.t) -> 'a t -> Sexplib0.Sexp.t
Smart constructors that simplify away constants whenever possible
module type Constructors = sig ... end
include Constructors
val base : 'a -> 'a t
val true_ : _ t
val false_ : _ t
val constant : Base.Bool.t -> _ t
function true -> true_ | false -> false_
val and_ : 'a t Base.List.t -> 'a t
n-ary And
val or_ : 'a t Base.List.t -> 'a t
n-ary Or
module O : sig ... end
val constant_value : 'a t -> Base.Bool.t Base.Option.t
constant_value t = Some b
iff t = constant b
val gather_conjuncts : 'a t -> 'a t Base.List.t
gather_conjuncts t
gathers up all toplevel conjuncts in t
. For example,
gather_conjuncts (and_ ts) = ts
gather_conjuncts (And (t1, t2)) = gather_conjuncts t1 @ gather_conjuncts t2
gather_conjuncts True = []
gather_conjuncts t = [t]
whent
matches neitherAnd (_, _)
norTrue
val gather_disjuncts : 'a t -> 'a t Base.List.t
gather_disjuncts t
gathers up all toplevel disjuncts in t
. For example,
gather_disjuncts (or_ ts) = ts
gather_disjuncts (Or (t1, t2)) = gather_disjuncts t1 @ gather_disjuncts t2
gather_disjuncts False = []
gather_disjuncts t = [t]
whent
matches neitherOr (_, _)
norFalse
include Container.S1 with type 'a t := 'a t
val mem : 'a t -> 'a -> equal:('a -> 'a -> bool) -> bool
Checks whether the provided element is there, using equal
.
val length : 'a t -> int
val is_empty : 'a t -> bool
val iter : 'a t -> f:('a -> unit) -> unit
val fold : 'a t -> init:'accum -> f:('accum -> 'a -> 'accum) -> 'accum
fold t ~init ~f
returns f (... f (f (f init e1) e2) e3 ...) en
, where e1..en
are the elements of t
val fold_result : 'a t -> init:'accum -> f:('accum -> 'a -> ('accum, 'e) Base.Result.t) -> ('accum, 'e) Base.Result.t
fold_result t ~init ~f
is a short-circuiting version of fold
that runs in the Result
monad. If f
returns an Error _
, that value is returned without any additional invocations of f
.
val fold_until : 'a t -> init:'accum -> f:('accum -> 'a -> ('accum, 'final) Base__Container_intf.Export.Continue_or_stop.t) -> finish:('accum -> 'final) -> 'final
fold_until t ~init ~f ~finish
is a short-circuiting version of fold
. If f
returns Stop _
the computation ceases and results in that value. If f
returns Continue _
, the fold will proceed. If f
never returns Stop _
, the final result is computed by finish
.
Example:
type maybe_negative =
| Found_negative of int
| All_nonnegative of { sum : int }
(** [first_neg_or_sum list] returns the first negative number in [list], if any,
otherwise returns the sum of the list. *)
let first_neg_or_sum =
List.fold_until ~init:0
~f:(fun sum x ->
if x < 0
then Stop (Found_negative x)
else Continue (sum + x))
~finish:(fun sum -> All_nonnegative { sum })
;;
let x = first_neg_or_sum [1; 2; 3; 4; 5]
val x : maybe_negative = All_nonnegative {sum = 15}
let y = first_neg_or_sum [1; 2; -3; 4; 5]
val y : maybe_negative = Found_negative -3
val exists : 'a t -> f:('a -> bool) -> bool
Returns true
if and only if there exists an element for which the provided function evaluates to true
. This is a short-circuiting operation.
val for_all : 'a t -> f:('a -> bool) -> bool
Returns true
if and only if the provided function evaluates to true
for all elements. This is a short-circuiting operation.
val count : 'a t -> f:('a -> bool) -> int
Returns the number of elements for which the provided function evaluates to true.
val sum : (module Base__Container_intf.Summable with type t = 'sum) -> 'a t -> f:('a -> 'sum) -> 'sum
Returns the sum of f i
for all i
in the container.
val find : 'a t -> f:('a -> bool) -> 'a option
Returns as an option
the first element for which f
evaluates to true.
val find_map : 'a t -> f:('a -> 'b option) -> 'b option
Returns the first evaluation of f
that returns Some
, and returns None
if there is no such element.
val to_list : 'a t -> 'a list
val to_array : 'a t -> 'a array
val min_elt : 'a t -> compare:('a -> 'a -> int) -> 'a option
Returns a minimum (resp maximum) element from the collection using the provided compare
function, or None
if the collection is empty. In case of a tie, the first element encountered while traversing the collection is returned. The implementation uses fold
so it has the same complexity as fold
.
val max_elt : 'a t -> compare:('a -> 'a -> int) -> 'a option
include Quickcheckable.S1 with type 'a t := 'a t
val quickcheck_generator : 'a Base_quickcheck.Generator.t -> 'a t Base_quickcheck.Generator.t
val quickcheck_observer : 'a Base_quickcheck.Observer.t -> 'a t Base_quickcheck.Observer.t
val quickcheck_shrinker : 'a Base_quickcheck.Shrinker.t -> 'a t Base_quickcheck.Shrinker.t
Blang.t
sports a substitution monad:
t >>= f
returns a computation that sequences the computations represented by two monad elements. The resulting computation first does t
to yield a value v
, and then runs the computation returned by f v
.
module Monad_infix : sig ... end
val return : 'a -> 'a t
return v
returns the (trivial) computation that returns v.
ignore_m t
is map t ~f:(fun _ -> ())
. ignore_m
used to be called ignore
, but we decided that was a bad name, because it shadowed the widely used Caml.ignore
. Some monads still do let ignore = ignore_m
for historical reasons.
module Let_syntax : sig ... end
val values : 'a t -> 'a Base.List.t
values t
forms the list containing every v
for which Base v
is a subexpression of t
val eval : 'a t -> ('a -> Base.Bool.t) -> Base.Bool.t
eval t f
evaluates the proposition t
relative to an environment f
that assigns truth values to base propositions.
val eval_set : universe:('elt, 'comparator) Set.t Lazy.t -> ('a -> ('elt, 'comparator) Set.t) -> 'a t -> ('elt, 'comparator) Set.t
eval_set ~universe set_of_base expression
returns the subset of elements e
in universe
that satisfy eval expression (fun base -> Set.mem (set_of_base base) e)
.
eval_set
assumes, but does not verify, that set_of_base
always returns a subset of universe
. If this doesn't hold, then eval_set
's result may contain elements not in universe
.
And set1 set2
represents the elements that are both in set1
and set2
, thus in the intersection of the two sets. Symmetrically, Or set1 set2
represents the union of set1
and set2
.
val specialize : 'a t -> ('a -> [ `Known of Base.Bool.t | `Unknown ]) -> 'a t
specialize t f
partially evaluates t
according to a perhaps-incomplete assignment f
of the values of base propositions. The following laws (at least partially) characterize its behavior.
specialize t (fun _ -> `Unknown) = t
specialize t (fun x -> `Known (f x)) = constant (eval t f)
List.for_all (values (specialize t g)) ~f:(fun x -> g x = `Unknown)
if List.for_all (values t) ~f:(fun x -> match g x with | `Known b -> b = f x | `Unknown -> true) then eval t f = eval (specialize t g) f
val invariant : 'a t -> Base.Unit.t
module Stable : sig ... end