StringLabels(3)

NAME
StringLabels - String operations.

Module
Module StringLabels

Documentation

Module StringLabels
 : sig end

String operations.

val length : string -> int

Return the length (number of characters) of the given string.

val get : string -> int -> char

String.get s n returns character number n in string s . The first character is character number 0. The last character is character number String.length s - 1 . You can also write s.[n] instead of String.get s n .

Raise Invalid_argument index out of bounds if n is outside the range 0 to (String.length s - 1) .

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

String.set s n c modifies string s in place, replacing the character number n by c . You can also write s.[n] <- c instead of String.set s n c . Raise Invalid_argument index out of bounds if n is outside the range 0 to (String.length s - 1) .

val create : int -> string

String.create n returns a fresh string of length n . The string initially contains arbitrary characters. Raise Invalid_argument if n < 0 or n > Sys.max_string_length .

val make : int -> char -> string

String.make n c returns a fresh string of length n , filled with the character c . Raise Invalid_argument if n < 0 or n > Sys.max_string_length .

val copy : string -> string

Return a copy of the given string.

val sub : string -> pos:int -> len:int -> string

String.sub s start len returns a fresh string of length len , containing the characters number start to start + len - 1 of string s . Raise Invalid_argument if start and len do not designate a valid substring of s ; that is, if start < 0 , or len < 0 , or start + len > StringLabels.length s .

val fill : string -> pos:int -> len:int -> char -> unit

String.fill s start len c modifies string s in place, replacing the characters number start to start + len - 1 by c . Raise Invalid_argument if start and len do not designate a valid substring of s .

val blit : src:string -> src_pos:int -> dst:string -> dst_pos:int -> len:int -> unit

String.blit src srcoff dst dstoff len copies len characters from string src , starting at character number srcoff , to string dst , starting at character number dstoff . It works correctly even if src and dst are the same string, and the source and destination chunks overlap. Raise Invalid_argument if srcoff and len do not designate a valid substring of src , or if dstoff and len do not designate a valid substring of dst .

val concat : sep:string -> string list -> string

String.concat sep sl concatenates the list of strings sl , inserting the separator string sep between each.

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

String.iter f s applies function f in turn to all the characters of s . It is equivalent to f s.[0]; f s.[1]; ...; f s.[String.length s - 1]; () .

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

Same as String.iter , but the function is applied to the index of the element as first argument (counting from 0), and the character itself as second argument.

Since 4.00.0

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

String.map f s applies function f in turn to all the characters of s and stores the results in a new string that is returned.

Since 4.00.0

val trim : string -> string

Return a copy of the argument, without leading and trailing whitespace. The characters regarded as whitespace are: ' ' , '\012' , '\n' , '\r' , and '\t' . If there is no whitespace character in the argument, return the original string itself, not a copy.

Since 4.00.0

val escaped : string -> string

Return a copy of the argument, with special characters represented by escape sequences, following the lexical conventions of OCaml. If there is no special character in the argument, return the original string itself, not a copy.

val index : string -> char -> int

String.index s c returns the position of the leftmost occurrence of character c in string s . Raise Not_found if c does not occur in s .

val rindex : string -> char -> int

String.rindex s c returns the position of the rightmost occurrence of character c in string s . Raise Not_found if c does not occur in s .

val index_from : string -> int -> char -> int

Same as StringLabels.index , but start searching at the character position given as second argument. String.index s c is equivalent to String.index_from s 0 c .

val rindex_from : string -> int -> char -> int

Same as StringLabels.rindex , but start searching at the character position given as second argument. String.rindex s c is equivalent to String.rindex_from s (String.length s - 1) c .

val contains : string -> char -> bool

String.contains s c tests if character c appears in the string s .

val contains_from : string -> int -> char -> bool

String.contains_from s start c tests if character c appears in the substring of s starting from start to the end of s . Raise Invalid_argument if start is not a valid index of s .

val rcontains_from : string -> int -> char -> bool

String.rcontains_from s stop c tests if character c appears in the substring of s starting from the beginning of s to index stop . Raise Invalid_argument if stop is not a valid index of s .

val uppercase : string -> string

Return a copy of the argument, with all lowercase letters translated to uppercase, including accented letters of the ISO Latin-1 (8859-1) character set.

val lowercase : string -> string

Return a copy of the argument, with all uppercase letters translated to lowercase, including accented letters of the ISO Latin-1 (8859-1) character set.

val capitalize : string -> string

Return a copy of the argument, with the first character set to uppercase.

val uncapitalize : string -> string

Return a copy of the argument, with the first character set to lowercase.

type t = string

An alias for the type of strings.

val compare : t -> t -> int

The comparison function for strings, with the same specification as Pervasives.compare . Along with the type t , this function compare allows the module String to be passed as argument to the functors Set.Make and Map.Make .