Documentation
containers lib
CCGen
Module
Values of type 'a Gen.t represent a possibly infinite sequence of values of type 'a. One can only iterate once on the sequence, as it is consumed by iteration/deconstruction/access. None is returned when the generator is exhausted. Most functions consume elements.
The submodule Restartrestartable generators , that is, functions unit -> 'a Gen.t that allow to build as many generators from the same source as needed.
type 'a t = unit -> 'a option A generator may be called several times, yielding the next value each time. It returns None when no elements remain
NOTE : version informations ("@since" annotations) in CCGen_intf will not be reliable, for they will represent versions of Gen rather than containers.
val get : 'a t -> 'a optionval next : 'a t -> 'a optionGet the next value, or fails
Drop the next value, discarding it.
val repeatedly : (unit -> 'a ) -> 'a t Call the same function an infinite number of times (useful for instance if the function is a random generator).
Operations on transient generators
include S with type 'a t := 'a gen Empty generator, with no elements
val singleton : 'a -> 'a gen val repeat : 'a -> 'a gen Repeat same element endlessly
val iterate : 'a -> ('a -> 'a ) -> 'a gen iterate x f is [x; f x; f (f x); f (f (f x)); ...]
val unfold : ('b -> ('a * 'b ) option -> 'b -> 'a gen Dual of fold'b value into a new 'b, and a 'a which is yielded, until None is returned.
val init : ?limit :int -> (int -> 'a ) -> 'a gen Calls the function, starting from 0, on increasing indices. If limit is provided and is a positive int, iteration will stop at the limit (excluded). For instance init ~limit:4 id will yield 0, 1, 2, and 3.
val is_empty : _ gen -> Check whether the enum is empty. Pops an element, if any
val fold : ('b -> 'a -> 'b ) -> 'b -> 'a gen -> 'b Fold on the generator, tail-recursively. Consumes the generator.
val reduce : ('a -> 'a -> 'a ) -> 'a gen -> 'a Fold on non-empty sequences. Consumes the generator.
val scan : ('b -> 'a -> 'b ) -> 'b -> 'a gen -> 'b gen Like fold
val unfold_scan : ('b -> 'a -> 'b * 'c ) -> 'b -> 'a gen -> 'c gen A mix of unfoldscan
val iter : ('a -> -> 'a gen -> Iterate on the enum, consumes it.
val iteri : (int -> 'a -> -> 'a gen -> Iterate on elements with their index in the enum, from 0, consuming it.
val length : _ gen -> Length of an enum (linear time), consuming it
val map : ('a -> 'b ) -> 'a gen -> 'b gen Lazy map. No iteration is performed now, the function will be called when the result is traversed.
Append the two enums; the result contains the elements of the first, then the elements of the second enum.
Flatten the enumeration of generators
Monadic bind; each element is transformed to a sub-enum which is then iterated on, before the next element is processed, and so on.
val mem : ?eq :('a -> 'a -> -> 'a -> 'a gen -> Is the given element, member of the enum?
val take : int -> 'a gen -> 'a gen val drop : int -> 'a gen -> 'a gen val nth : int -> 'a gen -> 'a n-th element, or Not_found
val take_nth : int -> 'a gen -> 'a gen take_nth n g returns every element of g whose index is a multiple of n. For instance take_nth 2 (1--10) |> to_list will return 1;3;5;7;9
val filter : ('a -> -> 'a gen -> 'a gen Filter out elements that do not satisfy the predicate.
val take_while : ('a -> -> 'a gen -> 'a gen Take elements while they satisfy the predicate
val drop_while : ('a -> -> 'a gen -> 'a gen Drop elements while they satisfy the predicate
val filter_map : ('a -> 'b option -> 'a gen -> 'b gen Maps some elements to 'b, drop the other ones
val zip_index : 'a gen -> (int * 'a ) gen Zip elements with their index in the enum
Unzip into two sequences, splitting each pair
val partition : ('a -> -> 'a gen -> 'a gen 'a gen partition p l returns the elements that satisfy p, and the elements that do not satisfy p
val for_all : ('a -> -> 'a gen -> Is the predicate true for all elements?
val exists : ('a -> -> 'a gen -> Is the predicate true for at least one element?
val min : ?lt :('a -> 'a -> -> 'a gen -> 'a Minimum element, according to the given comparison function.
val max : ?lt :('a -> 'a -> -> 'a gen -> 'a val eq : ?eq :('a -> 'a -> -> 'a gen -> 'a gen -> val lexico : ?cmp :('a -> 'a -> -> 'a gen -> 'a gen -> Lexicographic comparison of generators. If a generator is a prefix of the other one, it is considered smaller.
val compare : ?cmp :('a -> 'a -> -> 'a gen -> 'a gen -> val find : ('a -> -> 'a gen -> 'a optionfind p e returns the first element of e to satisfy p, or None.
val map2 : ('a -> 'b -> 'c ) -> 'a gen -> 'b gen -> 'c gen Map on the two sequences. Stops once one of them is exhausted.
val iter2 : ('a -> 'b -> -> 'a gen -> 'b gen -> Iterate on the two sequences. Stops once one of them is exhausted.
val fold2 : ('acc -> 'a -> 'b -> 'acc ) -> 'acc -> 'a gen -> 'b gen -> 'acc Fold the common prefix of the two iterators
val for_all2 : ('a -> 'b -> -> 'a gen -> 'b gen -> Succeeds if all pairs of elements satisfy the predicate. Ignores elements of an iterator if the other runs dry.
val exists2 : ('a -> 'b -> -> 'a gen -> 'b gen -> Succeeds if some pair of elements satisfy the predicate. Ignores elements of an iterator if the other runs dry.
val zip_with : ('a -> 'b -> 'c ) -> 'a gen -> 'b gen -> 'c gen Combine common part of the enums (stops when one is exhausted)
Zip together the common part of the enums
Pick elements fairly in each sub-generator. The merge of enums e1, e2, ... picks elements in e1, e2, in e3, e1, e2 .... Once a generator is empty, it is skipped; when they are all empty, and none remains in the input, their merge is also empty. For instance, merge [1;3;5] [2;4;6] will be, in disorder, 1;2;3;4;5;6.
val intersection : ?cmp :('a -> 'a -> -> 'a gen -> 'a gen -> 'a gen Intersection of two sorted sequences. Only elements that occur in both inputs appear in the output
val sorted_merge : ?cmp :('a -> 'a -> -> 'a gen -> 'a gen -> 'a gen Merge two sorted sequences into a sorted sequence
val sorted_merge_n : ?cmp :('a -> 'a -> -> 'a gen -> 'a gen Sorted merge of multiple sorted sequences
Duplicate the enum into n generators (default 2). The generators share the same underlying instance of the enum, so the optimal case is when they are consumed evenly
Split the enum into n generators in a fair way. Elements with index = k mod n with go to the k-th enum. n default value is 2.
interleave a b yields an element of a, then an element of b, and so on. When a generator is exhausted, this behaves like the other generator.
val intersperse : 'a -> 'a gen -> 'a gen Put the separator element between all elements of the given enum
val product : 'a gen -> 'b gen -> ('a * 'b ) gen Cartesian product, in no predictable order. Works even if some of the arguments are infinite.
val group : ?eq :('a -> 'a -> -> 'a gen -> 'a listgen Group equal consecutive elements together.
val uniq : ?eq :('a -> 'a -> -> 'a gen -> 'a gen Remove consecutive duplicate elements. Basically this is like fun e -> map List.hd (group e).
val sort : ?cmp :('a -> 'a -> -> 'a gen -> 'a gen Sort according to the given comparison function. The enum must be finite.
val sort_uniq : ?cmp :('a -> 'a -> -> 'a gen -> 'a gen Sort and remove duplicates. The enum must be finite.
val chunks : int -> 'a gen -> 'a arraygen chunks n e returns a generator of arrays of length n, composed of successive elements of e. The last array may be smaller than n
val permutations : 'a gen -> 'a listgen Permutations of the enum.
val combinations : int -> 'a gen -> 'a listgen Combinations of given length. The ordering of the elements within each combination is unspecified. Example (ignoring ordering): combinations 2 (1--3) |> to_list = [[1;2]; [1;3]; [2;3]]
val power_set : 'a gen -> 'a listgen All subsets of the enum (in no particular order). The ordering of the elements within each subset is unspecified.
val of_list : 'a list-> 'a gen Enumerate elements of the list
val to_list : 'a gen -> 'a listnon tail-call trasnformation to list, in the same order
val to_rev_list : 'a gen -> 'a listTail call conversion to list, in reverse order (more efficient)
val to_array : 'a gen -> 'a arrayConvert the enum to an array (not very efficient)
val of_array : ?start :int -> ?len :int -> 'a array-> 'a gen Iterate on (a slice of) the given array
val rand_int : int -> int gen Random ints in the given range.
val int_range : int -> int -> int gen int_range a b enumerates integers between a and b, included. a is assumed to be smaller than b.
module Infix : sig ... end val (--) : int -> int -> int gen Pretty print the content of the generator on a formatter.
Store content of the transient generator in memory, to be able to iterate on it several times later. If possible, consider using combinators from Restart
Same as persistent
Create a new transient generator. start gen is the same as gen () but is included for readability.