package octez-libs

  1. Overview
  2. Docs
package octez-libs
Legend:
Page
Library
Module
Module type
Parameter
Class
Class type
Source

Module TzPervasives.StringSource

include module type of String

Strings

Sourcetype t = string

The type for strings.

Sourceval make : int -> char -> string

make n c is a string of length n with each index holding the character c.

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

init n f is a string of length n with index i holding the character f i (called in increasing index order).

  • since 4.02.0
Sourceval empty : string

The empty string.

  • since 4.13.0
Sourceval of_bytes : bytes -> string

Return a new string that contains the same bytes as the given byte sequence.

  • since 4.13.0
Sourceval to_bytes : string -> bytes

Return a new byte sequence that contains the same bytes as the given string.

  • since 4.13.0
Sourceval length : string -> int

length s is the length (number of bytes/characters) of s.

Sourceval get : string -> int -> char

get s i is the character at index i in s. This is the same as writing s.[i].

Concatenating

Note. The Stdlib.(^) binary operator concatenates two strings.

Sourceval concat : string -> string list -> string

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

Sourceval cat : string -> string -> string

cat s1 s2 concatenates s1 and s2 (s1 ^ s2).

  • since 4.13.0

Predicates and comparisons

Sourceval equal : t -> t -> bool

equal s0 s1 is true if and only if s0 and s1 are character-wise equal.

  • since 4.03.0 (4.05.0 in StringLabels)
Sourceval compare : t -> t -> int

compare s0 s1 sorts s0 and s1 in lexicographical order. compare behaves like Stdlib.compare on strings but may be more efficient.

Sourceval starts_with : prefix:string -> string -> bool

starts_with ~prefix s is true if and only if s starts with prefix.

  • since 4.13.0
Sourceval ends_with : suffix:string -> string -> bool

ends_with ~suffix s is true if and only if s ends with suffix.

  • since 4.13.0
Sourceval contains_from : string -> int -> char -> bool

contains_from s start c is true if and only if c appears in s after position start.

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

rcontains_from s stop c is true if and only if c appears in s before position stop+1.

Sourceval contains : string -> char -> bool

contains s c is String.contains_from s 0 c.

Extracting substrings

Sourceval sub : string -> int -> int -> string

sub s pos len is a string of length len, containing the substring of s that starts at position pos and has length len.

Sourceval split_on_char : char -> string -> string list

split_on_char sep s is the list of all (possibly empty) substrings of s that are delimited by the character sep.

The function's result is specified by the following invariants:

  • The list is not empty.
  • Concatenating its elements using sep as a separator returns a string equal to the input (concat (make 1 sep) (split_on_char sep s) = s).
  • No string in the result contains the sep character.
  • since 4.04.0 (4.05.0 in StringLabels)

Transforming

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

map f s is the string resulting from applying f to all the characters of s in increasing order.

  • since 4.00.0
Sourceval mapi : (int -> char -> char) -> string -> string

mapi f s is like map but the index of the character is also passed to f.

  • since 4.02.0
Sourceval fold_right : (char -> 'a -> 'a) -> string -> 'a -> 'a

fold_right f s x computes f s.[0] (f s.[1] ( ... (f s.[n-1] x) ...)), where n is the length of the string s.

  • since 4.13.0
Sourceval for_all : (char -> bool) -> string -> bool

for_all p s checks if all characters in s satisfy the predicate p.

  • since 4.13.0
Sourceval exists : (char -> bool) -> string -> bool

exists p s checks if at least one character of s satisfies the predicate p.

  • since 4.13.0
Sourceval trim : string -> string

trim s is s without leading and trailing whitespace. Whitespace characters are: ' ', '\x0C' (form feed), '\n', '\r', and '\t'.

  • since 4.00.0
Sourceval escaped : string -> string

escaped s is s with special characters represented by escape sequences, following the lexical conventions of OCaml.

All characters outside the US-ASCII printable range [0x20;0x7E] are escaped, as well as backslash (0x2F) and double-quote (0x22).

The function Scanf.unescaped is a left inverse of escaped, i.e. Scanf.unescaped (escaped s) = s for any string s (unless escaped s fails).

Sourceval uppercase_ascii : string -> string

uppercase_ascii s is s with all lowercase letters translated to uppercase, using the US-ASCII character set.

  • since 4.03.0 (4.05.0 in StringLabels)
Sourceval lowercase_ascii : string -> string

lowercase_ascii s is s with all uppercase letters translated to lowercase, using the US-ASCII character set.

  • since 4.03.0 (4.05.0 in StringLabels)
Sourceval capitalize_ascii : string -> string

capitalize_ascii s is s with the first character set to uppercase, using the US-ASCII character set.

  • since 4.03.0 (4.05.0 in StringLabels)
Sourceval uncapitalize_ascii : string -> string

uncapitalize_ascii s is s with the first character set to lowercase, using the US-ASCII character set.

  • since 4.03.0 (4.05.0 in StringLabels)

Traversing

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

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.[length s - 1]; ().

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

iteri is like iter, but the function is also given the corresponding character index.

  • since 4.00.0

Searching

Sourceval index_from : string -> int -> char -> int

index_from s i c is the index of the first occurrence of c in s after position i.

  • raises Not_found

    if c does not occur in s after position i.

Sourceval index_from_opt : string -> int -> char -> int option

index_from_opt s i c is the index of the first occurrence of c in s after position i (if any).

  • since 4.05
Sourceval rindex_from : string -> int -> char -> int

rindex_from s i c is the index of the last occurrence of c in s before position i+1.

  • raises Not_found

    if c does not occur in s before position i+1.

Sourceval rindex_from_opt : string -> int -> char -> int option

rindex_from_opt s i c is the index of the last occurrence of c in s before position i+1 (if any).

  • since 4.05
Sourceval index : string -> char -> int

index s c is String.index_from s 0 c.

Sourceval index_opt : string -> char -> int option

index_opt s c is String.index_from_opt s 0 c.

  • since 4.05
Sourceval rindex : string -> char -> int

rindex s c is String.rindex_from s (length s - 1) c.

Sourceval rindex_opt : string -> char -> int option

rindex_opt s c is String.rindex_from_opt s (length s - 1) c.

  • since 4.05

Strings and Sequences

Sourceval to_seq : t -> char Seq.t

to_seq s is a sequence made of the string's characters in increasing order. In "unsafe-string" mode, modifications of the string during iteration will be reflected in the sequence.

  • since 4.07
Sourceval to_seqi : t -> (int * char) Seq.t

to_seqi s is like to_seq but also tuples the corresponding index.

  • since 4.07
Sourceval of_seq : char Seq.t -> t

of_seq s is a string made of the sequence's characters.

  • since 4.07

UTF decoding and validations

  • since 4.14

UTF-8

Sourceval get_utf_8_uchar : t -> int -> Uchar.utf_decode

get_utf_8_uchar b i decodes an UTF-8 character at index i in b.

Sourceval is_valid_utf_8 : t -> bool

is_valid_utf_8 b is true if and only if b contains valid UTF-8 data.

UTF-16BE

Sourceval get_utf_16be_uchar : t -> int -> Uchar.utf_decode

get_utf_16be_uchar b i decodes an UTF-16BE character at index i in b.

Sourceval is_valid_utf_16be : t -> bool

is_valid_utf_16be b is true if and only if b contains valid UTF-16BE data.

UTF-16LE

Sourceval get_utf_16le_uchar : t -> int -> Uchar.utf_decode

get_utf_16le_uchar b i decodes an UTF-16LE character at index i in b.

Sourceval is_valid_utf_16le : t -> bool

is_valid_utf_16le b is true if and only if b contains valid UTF-16LE data.

Deprecated functions

Sourceval create : int -> bytes

create n returns a fresh byte sequence of length n. The sequence is uninitialized and contains arbitrary bytes.

Sourceval set : bytes -> int -> char -> unit

set s n c modifies byte sequence s in place, replacing the byte at index n with c. You can also write s.[n] <- c instead of set s n c.

Sourceval blit : string -> int -> bytes -> int -> int -> unit

blit src src_pos dst dst_pos len copies len bytes from the string src, starting at index src_pos, to byte sequence dst, starting at character number dst_pos.

  • raises Invalid_argument

    if src_pos and len do not designate a valid range of src, or if dst_pos and len do not designate a valid range of dst.

Sourceval copy : string -> string

Return a copy of the given string.

  • deprecated

    Because strings are immutable, it doesn't make much sense to make identical copies of them.

Sourceval fill : bytes -> int -> int -> char -> unit

fill s pos len c modifies byte sequence s in place, replacing len bytes by c, starting at pos.

Sourceval 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.

  • deprecated

    Functions operating on Latin-1 character set are deprecated.

Sourceval 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.

  • deprecated

    Functions operating on Latin-1 character set are deprecated.

Sourceval capitalize : string -> string

Return a copy of the argument, with the first character set to uppercase, using the ISO Latin-1 (8859-1) character set..

  • deprecated

    Functions operating on Latin-1 character set are deprecated.

Sourceval uncapitalize : string -> string

Return a copy of the argument, with the first character set to lowercase, using the ISO Latin-1 (8859-1) character set.

  • deprecated

    Functions operating on Latin-1 character set are deprecated.

Binary decoding of integers

The functions in this section binary decode integers from strings.

All following functions raise Invalid_argument if the characters needed at index i to decode the integer are not available.

Little-endian (resp. big-endian) encoding means that least (resp. most) significant bytes are stored first. Big-endian is also known as network byte order. Native-endian encoding is either little-endian or big-endian depending on Sys.big_endian.

32-bit and 64-bit integers are represented by the int32 and int64 types, which can be interpreted either as signed or unsigned numbers.

8-bit and 16-bit integers are represented by the int type, which has more bits than the binary encoding. These extra bits are sign-extended (or zero-extended) for functions which decode 8-bit or 16-bit integers and represented them with int values.

Sourceval get_uint8 : string -> int -> int

get_uint8 b i is b's unsigned 8-bit integer starting at character index i.

  • since 4.13.0
Sourceval get_int8 : string -> int -> int

get_int8 b i is b's signed 8-bit integer starting at character index i.

  • since 4.13.0
Sourceval get_uint16_ne : string -> int -> int

get_uint16_ne b i is b's native-endian unsigned 16-bit integer starting at character index i.

  • since 4.13.0
Sourceval get_uint16_be : string -> int -> int

get_uint16_be b i is b's big-endian unsigned 16-bit integer starting at character index i.

  • since 4.13.0
Sourceval get_uint16_le : string -> int -> int

get_uint16_le b i is b's little-endian unsigned 16-bit integer starting at character index i.

  • since 4.13.0
Sourceval get_int16_ne : string -> int -> int

get_int16_ne b i is b's native-endian signed 16-bit integer starting at character index i.

  • since 4.13.0
Sourceval get_int16_be : string -> int -> int

get_int16_be b i is b's big-endian signed 16-bit integer starting at character index i.

  • since 4.13.0
Sourceval get_int16_le : string -> int -> int

get_int16_le b i is b's little-endian signed 16-bit integer starting at character index i.

  • since 4.13.0
Sourceval get_int32_ne : string -> int -> int32

get_int32_ne b i is b's native-endian 32-bit integer starting at character index i.

  • since 4.13.0
Sourceval get_int32_be : string -> int -> int32

get_int32_be b i is b's big-endian 32-bit integer starting at character index i.

  • since 4.13.0
Sourceval get_int32_le : string -> int -> int32

get_int32_le b i is b's little-endian 32-bit integer starting at character index i.

  • since 4.13.0
Sourceval get_int64_ne : string -> int -> int64

get_int64_ne b i is b's native-endian 64-bit integer starting at character index i.

  • since 4.13.0
Sourceval get_int64_be : string -> int -> int64

get_int64_be b i is b's big-endian 64-bit integer starting at character index i.

  • since 4.13.0
Sourceval get_int64_le : string -> int -> int64

get_int64_le b i is b's little-endian 64-bit integer starting at character index i.

  • since 4.13.0
include module type of Tezos_stdlib.TzString
Sourceval split : char -> ?limit:int -> string -> string list

split delim ~limit str splits str into a list of strings. Splitting occurs on delim characters (which are removed from output) at most limit times. Remaining delim characters are included in the last element of the resulting list.

limit defaults to max_int.

This function obeys the invariant that for all limits, delims and strs: String.concat (String.init 1 (fun _ -> delim)) (split delim ~limit str) = str.

Sourceval split_no_empty : char -> ?limit:int -> string -> string list

Splits a string on a delimiter character. It strips delimiters at the beginning and at the end. It considers groups of delimiters as one. If limit is passed, stops after limit split(s). limit defaults to max_int. It's guaranteed to never produce empty strings in the output. Therefore, it's capable of producing an empty list as a result.

For example, split_no_empty ',' ",hello,,world," returns "hello"; "world"

Sourceval chunk_bytes : ?error_on_partial_chunk:'a -> int -> bytes -> (string list, 'a) result

chunk_bytes n b chunks the sequence of bytes b into a list of strings, each of length n. The last chunk may be a non-empty string of length less than n, in which case the behaviour of the function depends on whether error_on_partial_chunk is set:

  • If error_on_partial_chunk is set, then the function returns Error error_on_partial_chunk,
  • Otherwise, the function return the list of chunks, where the last chunk is a non-empty string of length less than n.
Sourceval has_prefix : prefix:string -> string -> bool

true if input has prefix

Sourceval remove_prefix : prefix:string -> string -> string option

Some (input with prefix removed), if string has prefix, else None

Sourceval remove_suffix : suffix:string -> string -> string option

Some (input with suffix removed), if string has suffix, else None

Sourceval common_prefix : string -> string -> int

Length of common prefix of input strings

Sourceval mem_char : string -> char -> bool

Test whether a string contains a given character

Sourceval fold_left : ('a -> char -> 'a) -> 'a -> string -> 'a

Functional iteration over the characters of a string from first to last

Sourceval pp_bytes_hex : Format.formatter -> bytes -> unit

Pretty print bytes as hexadecimal string.

OCaml

Innovation. Community. Security.

GitHub Discord Twitter Peertube RSS
About
Changelog Releases Industrial Users Academic Users Why OCaml
Ecosystem
Packages Community Events OCaml Planet Jobs
Resources
Install OCaml Get Started Platform Tools Language Manual Standard Library API Books Exercises Papers OCaml Playground Logo
Policies
Carbon Footprint Governance Privacy Code of Conduct