Module Containers.String

module String: CCString

type 'a gen = unit -> 'a option

type 'a sequence = ('a -> unit) -> unit

type 'a klist = unit -> [ `Cons of 'a * 'a klist | `Nil ]

Common Signature

module type S = sig .. end

Strings

include String

val equal : string -> string -> bool

val compare : string -> string -> int

val hash : string -> int

val init : int -> (int -> char) -> string

Analog to Array.init.
Since 0.3.3

val rev : string -> string

rev s returns the reverse of s
Since 0.17

val pad : ?side:[ `Left | `Right ] -> ?c:char -> int -> string -> string

pad n str ensures that str is at least n bytes long, and pads it on the side with c if it's not the case.
Since 0.17

side : determines where padding occurs (default: `Left)

c : the char used to pad (default: ' ')

val of_char : char -> string

of_char 'a' = "a"
Since 0.19

val of_gen : char gen -> string

val of_seq : char sequence -> string

val of_klist : char klist -> string

val of_list : char list -> string

val of_array : char array -> string

val to_array : string -> char array

val find : ?start:int -> sub:string -> string -> int

Find sub in string, returns its first index or -1.

val find_all : ?start:int -> sub:string -> string -> int gen

find_all ~sub s finds all occurrences of sub in s, even overlapping instances.
Since 0.17

start : starting position in s

val find_all_l : ?start:int -> sub:string -> string -> int list

find_all ~sub s finds all occurrences of sub in s and returns them in a list
Since 0.17

start : starting position in s

val mem : ?start:int -> sub:string -> string -> bool

mem ~sub s is true iff sub is a substring of s
Since 0.12

val rfind : sub:string -> string -> int

Find sub in string from the right, returns its first index or -1. Should only be used with very small sub
Since 0.12

val replace : ?which:[ `All | `Left | `Right ] ->
       sub:string -> by:string -> string -> string

replace ~sub ~by s replaces some occurrences of sub by by in s
Since 0.14
Raises Invalid_argument if sub = ""

which : decides whether the occurrences to replace are:

`Left first occurrence from the left (beginning)
`Right first occurrence from the right (end)
`All all occurrences (default)

val is_sub : sub:string -> int -> string -> int -> len:int -> bool

is_sub ~sub i s j ~len returns true iff the substring of sub starting at position i and of length len is a substring of s starting at position j

val repeat : string -> int -> string

The same string, repeated n times

val prefix : pre:string -> string -> bool

prefix ~pre s returns true iff pre is a prefix of s

val suffix : suf:string -> string -> bool

suffix ~suf s returns true iff suf is a suffix of s
Since 0.7

val chop_prefix : pre:string -> string -> string option

chop_pref ~pre s removes pre from s if pre really is a prefix of s, returns None otherwise
Since 0.17

val chop_suffix : suf:string -> string -> string option

chop_suffix ~suf s removes suf from s if suf really is a suffix of s, returns None otherwise
Since 0.17

val take : int -> string -> string

take n s keeps only the n first chars of s
Since 0.17

val drop : int -> string -> string

drop n s removes the n first chars of s
Since 0.17

val take_drop : int -> string -> string * string

take_drop n s = take n s, drop n s
Since 0.17

val lines : string -> string list

lines s returns a list of the lines of s (splits along '\n')
Since 0.10

val lines_gen : string -> string gen

lines_gen s returns a generator of the lines of s (splits along '\n')
Since 0.10

val concat_gen : sep:string -> string gen -> string

concat_gen ~sep g concatenates all strings of g, separated with sep.
Since 0.10

val unlines : string list -> string

unlines l concatenates all strings of l, separated with '\n'
Since 0.10

val unlines_gen : string gen -> string

unlines_gen g concatenates all strings of g, separated with '\n'
Since 0.10

val set : string -> int -> char -> string

set s i c creates a new string which is a copy of s, except for index i, which becomes c.
Since 0.12
Raises Invalid_argument if i is an invalid index

val iter : (char -> unit) -> string -> unit

Alias to String.iter
Since 0.12

val iteri : (int -> char -> unit) -> string -> unit

Iter on chars with their index
Since 0.12

val map : (char -> char) -> string -> string

Map chars
Since 0.12

val mapi : (int -> char -> char) -> string -> string

Map chars with their index
Since 0.12

val filter_map : (char -> char option) -> string -> string

Since 0.17

val filter : (char -> bool) -> string -> string

Since 0.17

val flat_map : ?sep:string -> (char -> string) -> string -> string

Map each chars to a string, then concatenates them all
Since 0.12

sep : optional separator between each generated string

val for_all : (char -> bool) -> string -> bool

True for all chars?
Since 0.12

val exists : (char -> bool) -> string -> bool

True for some char?
Since 0.12

include CCString.S

val ltrim : t -> t

trim space on the left (see String.trim for more details)
Since 1.2

val rtrim : t -> t

trim space on the right (see String.trim for more details)
Since 1.2

Operations on 2 strings

val map2 : (char -> char -> char) -> string -> string -> string

Map pairs of chars
Since 0.12
Raises Invalid_argument if the strings have not the same length

val iter2 : (char -> char -> unit) -> string -> string -> unit

Iterate on pairs of chars
Since 0.12
Raises Invalid_argument if the strings have not the same length

val iteri2 : (int -> char -> char -> unit) -> string -> string -> unit

Iterate on pairs of chars with their index
Since 0.12
Raises Invalid_argument if the strings have not the same length

val fold2 : ('a -> char -> char -> 'a) -> 'a -> string -> string -> 'a

Fold on pairs of chars
Since 0.12
Raises Invalid_argument if the strings have not the same length

val for_all2 : (char -> char -> bool) -> string -> string -> bool

All pairs of chars respect the predicate?
Since 0.12
Raises Invalid_argument if the strings have not the same length

val exists2 : (char -> char -> bool) -> string -> string -> bool

Exists a pair of chars?
Since 0.12
Raises Invalid_argument if the strings have not the same length

Ascii functions

Those functions are deprecated in String since 4.03, so we provide a stable alias for them even in older versions

val capitalize_ascii : string -> string

See String.
Since 0.18

val uncapitalize_ascii : string -> string

See String.
Since 0.18

val uppercase_ascii : string -> string

See String.
Since 0.18

val lowercase_ascii : string -> string

See String.
Since 0.18

val equal_caseless : string -> string -> bool

Comparison without respect to ascii lowercase.
Since 1.2

Finding

A relatively efficient algorithm for finding sub-strings

module Find: sig .. end

Splitting

module Split: sig .. end

val split_on_char : char -> string -> string list

Split the string along the given char
Since 1.2

val split : by:string -> string -> string list

Alias to CCString.Split.list_cpy
Since 1.2

Utils

val compare_versions : string -> string -> int

compare_versions a b compares version strings a and b, considering that numbers are above text.
Since 0.13

val compare_natural : string -> string -> int

Natural Sort Order, comparing chunks of digits as natural numbers. https://en.wikipedia.org/wiki/Natural_sort_order
Since 1.3

val edit_distance : string -> string -> int

Edition distance between two strings. This satisfies the classical distance axioms: it is always positive, symmetric, and satisfies the formula distance a b + distance b c >= distance a c

Slices

A contiguous part of a string

module Sub: sig .. end