Module String_extended

Extensions to Core.Core_String.

val collate : string -> string -> int

collate s1 s2 sorts string in an order that's usaully more suited for human consumption by treating ints specially, e.g. it will output: ["rfc1.txt";"rfc822.txt";"rfc2086.txt"].

It works by splitting the strings in numerical and non-numerical chunks and comparing chunks two by two from left to right (and starting on a non numerical chunk):

  • Non_numerical chunks are compared using lexicographical ordering.
  • Numerical chunks are compared based on the values of the represented ints and the number of trailing zeros.

It is a total order.

val unescaped : ?⁠strict:bool -> string -> string

unescaped s is the inverse operation of escaped: it takes a string where all the special characters are escaped following the lexical convention of OCaml and returns an unescaped copy. The strict switch is on by default and makes the function treat illegal backslashes as errors. When strict is false every illegal backslash except escaped numeral greater than 255 is copied literally. The aforementioned numerals still raise errors. This mimics the behaviour of the ocaml lexer.

val unescaped_res : ?⁠strict:bool -> string -> (string, int * string) Core_kernel.Result.t

Same as unescaped but instead of raising Failure _ returns an error message with the position in the string in case of failure.

val squeeze : string -> string

squeeze str reduces all sequences of spaces, newlines, tabs, and carriage returns to single spaces.

val is_substring_deprecated : substring:string -> string -> bool

Use Core.String.is_substring instead of this function. This wrapper is here (for now) to maintain bug compatibility.

val pad_left : ?⁠char:char -> string -> int -> string

pad_left ~char s len Returns s padded to the length len by adding characters char to the left of the string. If s is already longer than len it is returned unchanged.

val pad_right : ?⁠char:char -> string -> int -> string
val line_break : len:int -> string -> string list

deprecated in favour of word_wrap

val word_wrap : ?⁠trailing_nl:bool -> ?⁠soft_limit:int -> ?⁠hard_limit:int -> ?⁠nl:string -> string -> string

word_wrap ~soft_limit s

Wraps the string so that it fits the length soft_limit. It doesn't break words unless we go over hard_limit.

if nl is passed it is inserted instead of the normal newline character.

val edit_distance : ?⁠transpose:unit -> string -> string -> int

Gives the Levenshtein distance between 2 strings, which is the number of insertions, deletions, and substitutions necessary to turn either string into the other. With the transpose argument, it also considers transpositions (Damerau-Levenshtein distance).