Module type `GenLabels_intf.S`Source

Sourcetype 'a t

Sourceval empty : 'a t

Empty generator, with no elements

Sourceval singleton : 'a -> 'a t

One-element generator

Sourceval return : 'a -> 'a t

Alias to singleton

since 0.3

Sourceval repeat : 'a -> 'a t

Repeat same element endlessly

Sourceval iterate : 'a -> ('a -> 'a) -> 'a t

iterate x f is [x; f x; f (f x); f (f (f x)); ...]

Sourceval unfold : ('b -> ('a * 'b) option) -> 'b -> 'a t

Dual of fold, with a deconstructing operation. It keeps on unfolding the 'b value into a new 'b, and a 'a which is yielded, until None is returned.

Sourceval init : ?limit:int -> (int -> 'a) -> 'a t

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.

Basic combinators

Note: those combinators, applied to generators (not restartable generators) consume their argument. Sometimes they consume it lazily, sometimes eagerly, but in any case once f gen has been called (with f a combinator), gen shouldn't be used anymore.

Sourceval is_empty : _ t -> bool

Check whether the gen is empty. Pops an element, if any

Sourceval fold : f:('b -> 'a -> 'b) -> init:'b -> 'a t -> 'b

Fold on the generator, tail-recursively. Consumes the generator.

Sourceval reduce : f:('a -> 'a -> 'a) -> 'a t -> 'a

Fold on non-empty sequences. Consumes the generator.

raises Invalid_argument
on an empty gen

Sourceval scan : f:('b -> 'a -> 'b) -> init:'b -> 'a t -> 'b t

Like fold, but keeping successive values of the accumulator. Consumes the generator.

Sourceval unfold_scan : ('b -> 'a -> 'b * 'c) -> 'b -> 'a t -> 'c t

A mix of unfold and scan. The current state is combined with the current element to produce a new state, and an output value of type 'c.

since 0.2.2

Sourceval iter : f:('a -> unit) -> 'a t -> unit

Iterate on the gen, consumes it.

Sourceval iteri : f:(int -> 'a -> unit) -> 'a t -> unit

Iterate on elements with their index in the gen, from 0, consuming it.

Sourceval length : _ t -> int

Length of an gen (linear time), consuming it

Sourceval map : f:('a -> 'b) -> 'a t -> 'b t

Lazy map. No iteration is performed now, the function will be called when the result is traversed.

Sourceval mapi : f:(int -> 'a -> 'b) -> 'a t -> 'b t

Lazy map with indexing starting from 0. No iteration is performed now, the function will be called when the result is traversed.

since 0.5

Sourceval fold_map : f:('b -> 'a -> 'b) -> init:'b -> 'a t -> 'b t

Lazy fold and map. No iteration is performed now, the function will be called when the result is traversed. The result is an iterator over the successive states of the fold.

since 0.2.4

Sourceval append : 'a t -> 'a t -> 'a t

Append the two gens; the result contains the elements of the first, then the elements of the second gen.

Sourceval flatten : 'a gen t -> 'a t

Flatten the generator of generators

Sourceval flat_map : f:('a -> 'b gen) -> 'a t -> 'b t

Monadic bind; each element is transformed to a sub-gen which is then iterated on, before the next element is processed, and so on.

Sourceval mem : ?eq:('a -> 'a -> bool) -> x:'a -> 'a t -> bool

Is the given element, member of the gen?

Sourceval take : int -> 'a t -> 'a t

Take at most n elements

Sourceval drop : int -> 'a t -> 'a t

Drop n elements

Sourceval nth : int -> 'a t -> 'a

n-th element, or Not_found

raises Not_found
if the generator contains less than n arguments

Sourceval take_nth : int -> 'a t -> 'a t

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

Sourceval filter : f:('a -> bool) -> 'a t -> 'a t

Filter out elements that do not satisfy the predicate.

Sourceval take_while : f:('a -> bool) -> 'a t -> 'a t

Take elements while they satisfy the predicate. The initial generator itself is not to be used anymore after this.

Source

val fold_while : 
  f:('a -> 'b -> 'a * [ `Stop | `Continue ]) ->
  init:'a ->
  'b t ->
  'a

Fold elements until ('a, `Stop) is indicated by the accumulator.

since 0.2.4

Sourceval drop_while : f:('a -> bool) -> 'a t -> 'a t

Drop elements while they satisfy the predicate. The initial generator itself should not be used anymore, only the result of drop_while.

Sourceval filter_map : f:('a -> 'b option) -> 'a t -> 'b t

Maps some elements to 'b, drop the other ones

Sourceval zip_index : 'a t -> (int * 'a) t

Zip elements with their index in the gen

Sourceval unzip : ('a * 'b) t -> 'a t * 'b t

Unzip into two sequences, splitting each pair

Sourceval partition : f:('a -> bool) -> 'a t -> 'a t * 'a t

partition p l returns the elements that satisfy p, and the elements that do not satisfy p

Sourceval for_all : f:('a -> bool) -> 'a t -> bool

Is the predicate true for all elements?

Sourceval exists : f:('a -> bool) -> 'a t -> bool

Is the predicate true for at least one element?

Sourceval min : ?lt:('a -> 'a -> bool) -> 'a t -> 'a

Minimum element, according to the given comparison function.

raises Invalid_argument
if the generator is empty

Sourceval max : ?lt:('a -> 'a -> bool) -> 'a t -> 'a

Maximum element, see min

raises Invalid_argument
if the generator is empty

Sourceval eq : ?eq:('a -> 'a -> bool) -> 'a t -> 'a t -> bool

Equality of generators.

Sourceval lexico : ?cmp:('a -> 'a -> int) -> 'a t -> 'a t -> int

Lexicographic comparison of generators. If a generator is a prefix of the other one, it is considered smaller.

Sourceval compare : ?cmp:('a -> 'a -> int) -> 'a t -> 'a t -> int

Synonym for lexico

Sourceval find : f:('a -> bool) -> 'a t -> 'a option

find p e returns the first element of e to satisfy p, or None.

Sourceval sum : int t -> int

Sum of all elements

Multiple iterators

Sourceval map2 : f:('a -> 'b -> 'c) -> 'a t -> 'b t -> 'c t

Map on the two sequences. Stops once one of them is exhausted.

Sourceval iter2 : f:('a -> 'b -> unit) -> 'a t -> 'b t -> unit

Iterate on the two sequences. Stops once one of them is exhausted.

Sourceval fold2 : f:('acc -> 'a -> 'b -> 'acc) -> init:'acc -> 'a t -> 'b t -> 'acc

Fold the common prefix of the two iterators

Sourceval for_all2 : f:('a -> 'b -> bool) -> 'a t -> 'b t -> bool

Succeeds if all pairs of elements satisfy the predicate. Ignores elements of an iterator if the other runs dry.

Sourceval exists2 : f:('a -> 'b -> bool) -> 'a t -> 'b t -> bool

Succeeds if some pair of elements satisfy the predicate. Ignores elements of an iterator if the other runs dry.

Sourceval zip_with : f:('a -> 'b -> 'c) -> 'a t -> 'b t -> 'c t

Combine common part of the gens (stops when one is exhausted)

Sourceval zip : 'a t -> 'b t -> ('a * 'b) t

Zip together the common part of the gens

Complex combinators

Sourceval merge : 'a gen t -> 'a t

Pick elements fairly in each sub-generator. The merge of gens 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.

Sourceval intersection : ?cmp:('a -> 'a -> int) -> 'a t -> 'a t -> 'a t

Intersection of two sorted sequences. Only elements that occur in both inputs appear in the output

Sourceval sorted_merge : ?cmp:('a -> 'a -> int) -> 'a t -> 'a t -> 'a t

Merge two sorted sequences into a sorted sequence

Sourceval sorted_merge_n : ?cmp:('a -> 'a -> int) -> 'a t list -> 'a t

Sorted merge of multiple sorted sequences

Sourceval tee : ?n:int -> 'a t -> 'a gen list

Duplicate the gen into n generators (default 2). The generators share the same underlying instance of the gen, so the optimal case is when they are consumed evenly

Sourceval round_robin : ?n:int -> 'a t -> 'a gen list

Split the gen into n generators in a fair way. Elements with index = k mod n with go to the k-th gen. n default value is 2.

Sourceval interleave : 'a t -> 'a t -> 'a t

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.

Sourceval intersperse : 'a -> 'a t -> 'a t

Put the separator element between all elements of the given gen

Sourceval product : 'a t -> 'b t -> ('a * 'b) t

Cartesian product, in no predictable order. Works even if some of the arguments are infinite.

Sourceval group : ?eq:('a -> 'a -> bool) -> 'a t -> 'a list t

Group equal consecutive elements together.

Sourceval uniq : ?eq:('a -> 'a -> bool) -> 'a t -> 'a t

Remove consecutive duplicate elements. Basically this is like fun e -> map List.hd (group e).

Sourceval sort : ?cmp:('a -> 'a -> int) -> 'a t -> 'a t

Sort according to the given comparison function. The gen must be finite.

Sourceval sort_uniq : ?cmp:('a -> 'a -> int) -> 'a t -> 'a t

Sort and remove duplicates. The gen must be finite.

Sourceval chunks : int -> 'a t -> 'a array t

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

Sourceval permutations : 'a t -> 'a list t

Permutations of the gen.

since 0.2.2

Sourceval permutations_heap : 'a t -> 'a array t

Permutations of the gen, using Heap's algorithm.

since 0.2.3

Sourceval combinations : int -> 'a t -> 'a list t

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]]

since 0.2.2

Sourceval power_set : 'a t -> 'a list t

All subsets of the gen (in no particular order). The ordering of the elements within each subset is unspecified.

since 0.2.2

Basic conversion functions

Sourceval of_list : 'a list -> 'a t

Enumerate elements of the list

Sourceval to_list : 'a t -> 'a list

non tail-call trasnformation to list, in the same order

Sourceval to_rev_list : 'a t -> 'a list

Tail call conversion to list, in reverse order (more efficient)

Sourceval to_array : 'a t -> 'a array

Convert the gen to an array (not very efficient)

Sourceval of_array : ?start:int -> ?len:int -> 'a array -> 'a t

Iterate on (a slice of) the given array

Sourceval of_string : ?start:int -> ?len:int -> string -> char t

Iterate on bytes of the string

Sourceval to_string : char t -> string

Convert into a string

Sourceval to_buffer : Buffer.t -> char t -> unit

Consumes the iterator and writes to the buffer

Sourceval rand_int : int -> int t

Random ints in the given range.

Sourceval int_range : ?step:int -> int -> int -> int t

int_range ~step a b generates integers between a and b, included, with steps of length step (1 if omitted). a is assumed to be smaller than b. step must not be null, but it can be negative for decreasing integers.

Sourceval lines : char t -> string t

Group together chars belonging to the same line

since 0.3

Sourceval unlines : string t -> char t

Explode lines into their chars, adding a '\n' after each one

since 0.3

Sourcemodule Infix : sig ... end

Sourceval (--) : int -> int -> int t

Synonym for int_range ~by:1

Sourceval (>>=) : 'a t -> ('a -> 'b gen) -> 'b t

Monadic bind operator

Sourceval (>>|) : 'a t -> ('a -> 'b) -> 'b t

Infix map operator

since 0.2.3

Sourceval (>|=) : 'a t -> ('a -> 'b) -> 'b t

Infix map operator

since 0.2.3

Source

val pp : 
  ?start:string ->
  ?stop:string ->
  ?sep:string ->
  ?horizontal:bool ->
  (Format.formatter -> 'a -> unit) ->
  Format.formatter ->
  'a t ->
  unit

Pretty print the content of the generator on a formatter.

Install

Dune Dependency

Authors

Maintainers

Sources

doc/gen/GenLabels_intf/module-type-S/index.html

Module type `GenLabels_intf.S`Source

Basic combinators

Multiple iterators

Complex combinators

Basic conversion functions

package gen

Install

Dune Dependency

Authors

Maintainers

Sources

doc/gen/GenLabels_intf/module-type-S/index.html

Module type GenLabels_intf.SSource

Basic combinators

Multiple iterators

Complex combinators

Basic conversion functions

Module type `GenLabels_intf.S`Source