Docs / API / Js / String

String

JavaScript String API

t

RESCRIPT

type t = string

make

RESCRIPT

let make: 'a => t

make(value) converts the given value to a string.

Examples

RESCRIPT
Js.String2.make(3.5) == "3.5"
Js.String2.make([1, 2, 3]) == "1,2,3"

fromCharCode

RESCRIPT

let fromCharCode: int => t

fromCharCode(n) creates a string containing the character corresponding to that number; n ranges from 0 to 65535. If out of range, the lower 16 bits of the value are used. Thus, fromCharCode(0x1F63A) gives the same result as fromCharCode(0xF63A). See String.fromCharCode on MDN.

Examples

RESCRIPT
Js.String2.fromCharCode(65) == "A"
Js.String2.fromCharCode(0x3c8) == `ψ`
Js.String2.fromCharCode(0xd55c) == `한`
Js.String2.fromCharCode(-64568) == `ψ`

fromCharCodeMany

RESCRIPT

let fromCharCodeMany: array<int> => t

fromCharCodeMany([n1, n2, n3]) creates a string from the characters corresponding to the given numbers, using the same rules as fromCharCode. See String.fromCharCode on MDN.

fromCodePoint

RESCRIPT

let fromCodePoint: int => t

fromCodePoint(n) creates a string containing the character corresponding to that numeric code point. If the number is not a valid code point, it raises RangeError.Thus, fromCodePoint(0x1F63A) will produce a correct value, unlike fromCharCode(0x1F63A), and fromCodePoint(-5) will raise a RangeError.

See String.fromCodePoint on MDN.

Examples

RESCRIPT
Js.String2.fromCodePoint(65) == "A"
Js.String2.fromCodePoint(0x3c8) == `ψ`
Js.String2.fromCodePoint(0xd55c) == `한`
Js.String2.fromCodePoint(0x1f63a) == `😺`

fromCodePointMany

RESCRIPT

let fromCodePointMany: array<int> => t

fromCodePointMany([n1, n2, n3]) creates a string from the characters corresponding to the given code point numbers, using the same rules as fromCodePoint.

See String.fromCodePoint on MDN.

Examples

RESCRIPT
Js.String2.fromCodePointMany([0xd55c, 0xae00, 0x1f63a]) == `한글😺`

length

RESCRIPT

let length: t => int

length(s) returns the length of the given string. See String.length on MDN.

Examples

RESCRIPT
Js.String2.length("abcd") == 4

get

RESCRIPT

let get: (t, int) => t

get(s, n) returns as a string the character at the given index number. If n is out of range, this function returns undefined, so at some point this function may be modified to return option<string>.

Examples

RESCRIPT
Js.String2.get("Reason", 0) == "R"
Js.String2.get("Reason", 4) == "o"
Js.String2.get(`Rẽasöń`, 5) == `ń`

charAt

RESCRIPT

let charAt: (int, t) => t

charCodeAt

RESCRIPT

let charCodeAt: (int, t) => float

codePointAt

RESCRIPT

let codePointAt: (int, t) => option<int>

concat

RESCRIPT

let concat: (t, t) => t

concatMany

RESCRIPT

let concatMany: (array<t>, t) => t

endsWith

RESCRIPT

let endsWith: (t, t) => bool

endsWithFrom

RESCRIPT

let endsWithFrom: (t, int, t) => bool

includes

RESCRIPT

let includes: (t, t) => bool

includesFrom

RESCRIPT

let includesFrom: (t, int, t) => bool

indexOf

RESCRIPT

let indexOf: (t, t) => int

indexOfFrom

RESCRIPT

let indexOfFrom: (t, int, t) => int

lastIndexOf

RESCRIPT

let lastIndexOf: (t, t) => int

lastIndexOfFrom

RESCRIPT

let lastIndexOfFrom: (t, int, t) => int

localeCompare

RESCRIPT

let localeCompare: (t, t) => float

match_

RESCRIPT

let match_: (Js_re.t, t) => option<array<option<t>>>

normalize

RESCRIPT

let normalize: t => t

normalize(str) returns the normalized Unicode string using Normalization Form Canonical (NFC) Composition. Consider the character ã, which can be represented as the single codepoint \u00e3 or the combination of a lower case letter A \u0061 and a combining tilde \u0303. Normalization ensures that both can be stored in an equivalent binary representation.

See String.normalize on MDN.

See also Unicode technical report #15 for details.

normalizeByForm

RESCRIPT

let normalizeByForm: (t, t) => t

repeat

RESCRIPT

let repeat: (int, t) => t

replace

RESCRIPT

let replace: (t, t, t) => t

replaceByRe

RESCRIPT

let replaceByRe: (Js_re.t, t, t) => t

unsafeReplaceBy0

RESCRIPT

let unsafeReplaceBy0: (Js_re.t, (t, int, t) => t, t) => t

unsafeReplaceBy1

RESCRIPT

let unsafeReplaceBy1: (Js_re.t, (t, t, int, t) => t, t) => t

unsafeReplaceBy2

RESCRIPT

let unsafeReplaceBy2: (Js_re.t, (t, t, t, int, t) => t, t) => t

unsafeReplaceBy3

RESCRIPT

let unsafeReplaceBy3: (Js_re.t, (t, t, t, t, int, t) => t, t) => t

search

RESCRIPT

let search: (Js_re.t, t) => int

slice

RESCRIPT

let slice: (~from: int, ~to_: int, t) => t

sliceToEnd

RESCRIPT

let sliceToEnd: (~from: int, t) => t

split

RESCRIPT

let split: (t, t) => array<t>

splitAtMost

RESCRIPT

let splitAtMost: (t, ~limit: int, t) => array<t>

splitByRe

RESCRIPT

let splitByRe: (Js_re.t, t) => array<option<t>>

splitByReAtMost

RESCRIPT

let splitByReAtMost: (Js_re.t, ~limit: int, t) => array<option<t>>

startsWith

RESCRIPT

let startsWith: (t, t) => bool

startsWithFrom

RESCRIPT

let startsWithFrom: (t, int, t) => bool

substr

RESCRIPT

let substr: (~from: int, t) => t

substrAtMost

RESCRIPT

let substrAtMost: (~from: int, ~length: int, t) => t

substring

RESCRIPT

let substring: (~from: int, ~to_: int, t) => t

substringToEnd

RESCRIPT

let substringToEnd: (~from: int, t) => t

toLowerCase

RESCRIPT

let toLowerCase: t => t

toLowerCase(str) converts str to lower case using the locale-insensitive case mappings in the Unicode Character Database. Notice that the conversion can give different results depending upon context, for example with the Greek letter sigma, which has two different lower case forms; one when it is the last character in a string and another when it is not.

See String.toLowerCase on MDN.

Examples

RESCRIPT
Js.String.toLowerCase("ABC") == "abc"
Js.String.toLowerCase(`ΣΠ`) == `σπ`
Js.String.toLowerCase(`ΠΣ`) == `πς`

toLocaleLowerCase

RESCRIPT

let toLocaleLowerCase: t => t

toLocaleLowerCase(str) converts str to lower case using the current locale.

See String.toLocaleLowerCase on MDN.

toUpperCase

RESCRIPT

let toUpperCase: t => t

toUpperCase(str) converts str to upper case using the locale-insensitive case mappings in the Unicode Character Database. Notice that the conversion can expand the number of letters in the result; for example the German ß capitalizes to two Ses in a row.

See String.toUpperCase on MDN.

Examples

RESCRIPT
Js.String.toUpperCase("abc") == "ABC"
Js.String.toUpperCase(`Straße`) == `STRASSE`
Js.String.toUpperCase(`πς`) == `ΠΣ`

toLocaleUpperCase

RESCRIPT

let toLocaleUpperCase: t => t

toLocaleUpperCase(str) converts str to upper case using the current locale.

See String.to:LocaleUpperCase on MDN.

trim

RESCRIPT

let trim: t => t

trim(str) returns a string that is str with whitespace stripped from both ends. Internal whitespace is not removed.

See String.trim on MDN.

Examples

RESCRIPT
Js.String.trim("   abc def   ") == "abc def"
Js.String.trim("\n\r\t abc def \n\n\t\r ") == "abc def"

anchor

RESCRIPT

let anchor: (t, t) => t

link

RESCRIPT

let link: (t, t) => t

castToArrayLike

RESCRIPT

let castToArrayLike: t => Js_array2.array_like<t>

Casts its argument to an array_like entity that can be processed by functions such as Js.Array2.fromMap()

Examples

RESCRIPT
let s = "abcde"
let arr = Js.Array2.fromMap(Js.String.castToArrayLike(s), x => x)
arr == ["a", "b", "c", "d", "e"]