is_valid_utf_16le b is true if and only if b contains valid UTF-16LE data.
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.
val get_uint8 : string ->int -> int
get_uint8 b i is b's unsigned 8-bit integer starting at character index i.
since 4.13
val get_int8 : string ->int -> int
get_int8 b i is b's signed 8-bit integer starting at character index i.
since 4.13
val 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
val 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
val 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
val 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
val 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
val 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
val get_int32_ne : string ->int -> int32
get_int32_ne b i is b's native-endian 32-bit integer starting at character index i.
A seeded hash function for strings, with the same output value as Hashtbl.seeded_hash. This function allows this module to be passed as argument to the functor Hashtbl.MakeSeeded.
since 5.0
val 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
val 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
val 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
val 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
val get_int64_le : string ->int -> int64
get_int64_le b i is b's little-endian 64-bit integer starting at character index i.
length s returns the length (number of characters) of the given string s.
val blit :
src:t->src_pos:int ->dst:Bytes.t->dst_pos:int ->len:int ->
unit
blit ~src ~src_pos ~dst ~dst_pos ~len copies len characters from string src starting at character indice src_pos, to the Bytes sequence dst starting at character indice dst_pos. Like String.blit. Compatible with the -safe-string option.
val is_sub :
sub:string ->sub_pos:int ->string ->pos:int ->sub_len:int ->
bool
is_sub ~sub ~sub_pos s ~pos ~sub_len returns true iff the substring of sub starting at position sub_pos and of length sub_len is a substring of s starting at position pos.
val repeat : string ->int -> string
repeat s n creates a string by repeating the string sn 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_prefix ~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 is 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').
iter ~f s applies function f on each character of s. Alias to String.iter.
since 0.12
val filter_map : f:(char ->char option)->string -> string
filter_map ~f s calls (f a0) (f a1) … (f an) where a0 … an are the characters of s. It returns the string of characters ci such as f ai = Some ci (when f returns None, the corresponding element of s is discarded).
since 0.17
val filter : f:(char -> bool)->string -> string
filter ~f s discards characters of s not satisfying f.
since 0.17
val uniq : eq:(char ->char -> bool)->string -> string
uniq ~eq s remove consecutive duplicate characters in s.
since 3.4
val flat_map : ?sep:string ->f:(char -> string)->string -> string
flat_map ?sep ~f s maps each chars of s to a string, then concatenates them all.
parametersep
optional separator between each generated string.
since 0.12
val for_all : f:(char -> bool)->string -> bool
for_all ~f s is true iff all characters of s satisfy the predicate f.
since 0.12
val exists : f:(char -> bool)->string -> bool
exists ~f s is true iff some character of s satisfy the predicate f.
val split_on_char : by:char ->string ->string list
split_on_char ~by s splits the string s along the given char by.
since 1.2
val split : by:string ->string ->string list
split ~by s splits the string s along the given string by. Alias to Split.list_cpy.
since 1.2
Utils
val compare_versions : string ->string -> int
compare_versions s1 s2 compares version stringss1 and s2, considering that numbers are above text.
since 0.13
val compare_natural : string ->string -> int
compare_natural s1 s2 is the Natural Sort Order, comparing chunks of digits as natural numbers. https://en.wikipedia.org/wiki/Natural_sort_order
since 1.3
val edit_distance : ?cutoff:int ->string ->string -> int
edit_distance ?cutoff s1 s2 is the edition distance between the two strings s1 and s2. This satisfies the classical distance axioms: it is always positive, symmetric, and satisfies the formula distance s1 s2 + distance s2 s3 >= distance s1 s3.
parametercutoff
if provided, it's a cap on both the number of iterations, and on the result. (since 3.0). This is useful if you just want to check whether the edit distance is less or equal than 2 (use cutoff of 3).