A [string] is a sequence of characters. ▌ 📦 [JSR](https://jsr.io/@nodef/extra-string), 📦 [NPM](https://www.npmjs.com/package/extra-string), 📰 [Docs](https://jsr.io/@nodef/extra-string/doc). In JavaScript, strings are not [mutable]. Any transfomation of a *string*, such as `slice` or `concat` generates a *new string*. The *JavaScript runtime* however may optimize this behavior by *mutating strings behind the scenes*, when it can be guarenteed that the previous string is *not accessible* to the programmer. The *runtime* may also *avoid copying slices* of a string, or even *concatenation of slices of* *strings*, by implementing it as a *series of lookups into existing strings*. Food for thought. This package provides **functions** for generating spaces, querying *about* a string, *comparing* strings, getting *parts* of a string, *searching* a string, *transforming* a string or its *case*, finding *ngrams* in strings, finding *similarity/distance* between strings, and array-like functions. All **built-in** string functions are also included. Finally, *constants* for *ASCII characters*, and *minimum/maximum code point* are included. [string]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/String [mutable]: https://developer.mozilla.org/en-US/docs/Glossary/Mutable
```javascript import * as xstring from "jsr:@nodef/extra-string"; xstring.longestCommonInfix('dismiss', 'mississipi'); // → 'miss' xstring.longestUncommonInfixes('chocolatier', 'engineer'); // → ['chocolati', 'engine'] xstring.toKebabCase('Malwa Plateau'); // → 'malwa-plateau' '6.626 x 10' + xstring.toSuperscript('-34'); // → '6.626 x 10⁻³⁴' (Planck's constant) xstring.tverskyDistance('pikachu', 'raichu', 3, 0.2, 0.4); // → 0.6666666666666667 ```

## Index | Name | Description | | ---- | ---- | | [toKebabCase] | Convert a string to kebab-case. | | [toSnakeCase] | Convert a string to snake-case. | | [toCamelCase] | Convert a string to camel-case. | | [toPascalCase] | Convert a string to pascal-case. | | [toSlugCase] | Convert a string to slug-case (URL-friendly kebab-case). | | [toWords] | Split a string into words, after de-casing it. | | | | | [toBaseline] | Convert a string to baseline characters (limited support). | | [toSuperscript] | Convert a string to superscript characters (limited support). | | [toSubscript] | Convert a string to superscript characters (limited support). | | | | | [ngrams] | Get n-grams of a string. | | [uniqueNgrams] | Find unique n-grams of a string. | | [countNgrams] | Count the total number of n-grams of a string. | | [countUniqueNgrams] | Count the total number of unique n-grams of a string. | | [countEachNgram] | Count each n-gram of a string. | | [matchingNgrams] | Get matching n-grams between strings. | | [uniqueMatchingNgrams] | Get unique matching n-grams between strings. | | [countMatchingNgrams] | Count the total number of matching n-grams between strings. | | [countEachMatchingNgram] | Count each matching n-gram between strings. | | [countUniqueMatchingNgrams] | Count the total number of unique matching n-grams between strings. | | | | | [euclideanDistance] | Get euclidean distance between strings. | | [hammingDistance] | Get hamming distance between strings. | | [jaccardIndex] | Get jaccard index between strings. | | [jaccardDistance] | Get jaccard distance between strings. | | [sorensenDiceIndex] | Get Sørensen-Dice index between strings. | | [sorensenDiceDistance] | Get Sørensen-Dice distance between strings. | | [tverskyIndex] | Get Tversky index between strings. | | [tverskyDistance] | Get Tversky distance between strings. | | [jaroSimilarity] | Get Jaro similarity between strings. | | [jaroDistance] | Get Jaro distance between strings. | | [jaroWinklerSimilarity] | Get Jaro-Winkler similarity between strings. | | [jaroWinklerDistance] | Get Jaro-Winkler distance between strings. | | [levenshteinDistance] | Get Levenshtein distance between strings. | | [damerauLevenshteinDistance] | Get Damerau–Levenshtein distance between strings. | | | | | [longestCommonInfix] | Get the longest common infix between strings. | | [longestCommonPrefix] | Get the longest common prefix of strings. | | [longestCommonSuffix] | Get the longest common suffix of strings. | | [longestUncommonInfixes] | Get the longest uncommon infixes of strings. | | | | | [get] | Get character at a given index in string. | | [getAll] | Get characters at indices. | | [set] | Write a substring at specified index in string. | | [begin] | Get leftmost part of string. | | [middle] | Get a portion of string from middle. | | [end] | Get rightmost part of string. | | | | | [fromCharCode] | Get characters whose UTF-16 code units are given. | | [fromCodePoint] | Get characters whose unicode code points are given. | | [concat] | Combine multiple strings into one. | | [repeat] | Repeat string given number of times. | | | | | [valueOf] | Get primitive value of string object. | | [length] | Get length of string. | | [charAt] | Get character at given index in string. | | [charCodeAt] | Get UTF-16 code unit of a character in string. | | [codePointAt] | Get unicode code point of a character in string. | | | | | [localeCompare] | Compare two strings in the current or given locale. | | | | | [includes] | Check if string has a given infix. | | [startsWith] | Check if string has a given prefix. | | [endsWith] | Check if string has a given suffix. | | [indexOf] | Get first index of a given infix in string. | | [lastIndexOf] | Get last index of a given infix in string. | | [search] | Get first index of regular expression match in string. | | [match] | Get results of matching string with regular expression. | | [matchAll] | Get detailed results of matching string with regular expression. | | | | | [toString] | Get string representation of string. | | | | | [slice] | Extract section of string. | | [substring] | Extract section of string. | | [split] | Split string by a given separator into substrings. | | | | | [cycle] | Get characters that cycle through string. | | [rotate] | Rotate characters in string. | | | | | [trimStart] | Remove whitespace from begining of string. | | [trimEnd] | Remove whitespace from end of string. | | [trim] | Remove whitespace from begining and end of string. | | [padStart] | Pad start of string to fit a desired length. | | [padEnd] | Pad end of string to fit a desired length. | | | | | [toUpperCase] | Convert string to upper case. | | [toLocaleUpperCase] | Convert string to upper case, as per locale-specific case mappings. | | [toLowerCase] | Convert string to lower case. | | [toLocaleLowerCase] | Convert string to lower case, as per locale-specific case mappings. | | | | | [replace] | Replace first match of given pattern by replacement. | | [normalize] | Normalize string by given form, as per Unicode Standard Annex #15. | | | | | [of] | Create string from arguments, like `Array.of()`. | | [from] | Create string from iterable, like `Array.from()`. | | | | | [splice] | Remove/replace characters in a string. | | [reverse] | Reverse a string. | | [sort] | Arrange characters in an order. | | | | | [filter] | Filter characters which pass a test. | | | | | [spaces] | Get a string of spaces. | | | | | [is] | Check if value is a string. | | [isEmpty] | Check if string is empty. | | [isCharacter] | Check if string is a character. | | [index] | Get non-negative index within string. | | [indexRange] | Get non-negative index range within string. | | [codePointRange] | Get unicode code point range of string. | | | | | [compare] | Compare two strings. | | [isEqual] | Check if two strings are equal. | | | | | [DIGITS] | Decimal digits 0-9. | | [OCT_DIGITS] | Octal digits 0-7. | | [HEX_DIGITS] | Hexadecimal digits 0-9, A-F, a-f. | | [UPPERCASE] | English letters A-Z. | | [LOWERCASE] | English letters a-z. | | [LETTERS] | Combination of uppercase, lowercase english letters. | | [PUNCTUATION] | Punctuation symbols (ASCII). | | [WHITESPACE] | The string "\t\n\x0b\x0c\r ". | | [PRINTABLE] | Combination of digits, letters, punctuation, and whitespace (ASCII). | | [MIN_CODE_POINT] | Minimum unicode code point. | | [MAX_CODE_POINT] | Maximum unicode code point. |

## References - [MDN Web docs](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference) - [Lodash documentation](https://lodash.com/docs/4.17.15) - [natural package by Chris Umbel and contributors](https://www.npmjs.com/package/natural) - [esrever package by Mathias Bynens and contributors](https://www.npmjs.com/package/esrever) - [js-string-compression package by Chen Caishun](https://github.com/cschen1205/js-string-compression) - [@stdlib/string-base-trim package by @stdlib-js](https://github.com/stdlib-js/string-base-trim) - [How do you reverse a string in-place in JavaScript?](https://stackoverflow.com/a/959004/1413259)

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https://jsr.io/@nodef/extra-string/doc/~/fromCodePoint [concat]: https://jsr.io/@nodef/extra-string/doc/~/concat [repeat]: https://jsr.io/@nodef/extra-string/doc/~/repeat [valueOf]: https://jsr.io/@nodef/extra-string/doc/~/valueOf [length]: https://jsr.io/@nodef/extra-string/doc/~/length [charAt]: https://jsr.io/@nodef/extra-string/doc/~/charAt [charCodeAt]: https://jsr.io/@nodef/extra-string/doc/~/charCodeAt [codePointAt]: https://jsr.io/@nodef/extra-string/doc/~/codePointAt [localeCompare]: https://jsr.io/@nodef/extra-string/doc/~/localeCompare [includes]: https://jsr.io/@nodef/extra-string/doc/~/includes [startsWith]: https://jsr.io/@nodef/extra-string/doc/~/startsWith [endsWith]: https://jsr.io/@nodef/extra-string/doc/~/endsWith [indexOf]: https://jsr.io/@nodef/extra-string/doc/~/indexOf [lastIndexOf]: https://jsr.io/@nodef/extra-string/doc/~/lastIndexOf [search]: https://jsr.io/@nodef/extra-string/doc/~/search [match]: https://jsr.io/@nodef/extra-string/doc/~/match [matchAll]: https://jsr.io/@nodef/extra-string/doc/~/matchAll [toString]: https://jsr.io/@nodef/extra-string/doc/~/toString [slice]: https://jsr.io/@nodef/extra-string/doc/~/slice [substring]: https://jsr.io/@nodef/extra-string/doc/~/substring [split]: https://jsr.io/@nodef/extra-string/doc/~/split [cycle]: https://jsr.io/@nodef/extra-string/doc/~/cycle [rotate]: https://jsr.io/@nodef/extra-string/doc/~/rotate [trimStart]: https://jsr.io/@nodef/extra-string/doc/~/trimStart [trimEnd]: https://jsr.io/@nodef/extra-string/doc/~/trimEnd [trim]: https://jsr.io/@nodef/extra-string/doc/~/trim [padStart]: https://jsr.io/@nodef/extra-string/doc/~/padStart [padEnd]: https://jsr.io/@nodef/extra-string/doc/~/padEnd [toUpperCase]: https://jsr.io/@nodef/extra-string/doc/~/toUpperCase [toLocaleUpperCase]: https://jsr.io/@nodef/extra-string/doc/~/toLocaleUpperCase [toLowerCase]: https://jsr.io/@nodef/extra-string/doc/~/toLowerCase [toLocaleLowerCase]: https://jsr.io/@nodef/extra-string/doc/~/toLocaleLowerCase [replace]: https://jsr.io/@nodef/extra-string/doc/~/replace [normalize]: https://jsr.io/@nodef/extra-string/doc/~/normalize [of]: https://jsr.io/@nodef/extra-string/doc/~/of [from]: https://jsr.io/@nodef/extra-string/doc/~/from [splice]: https://jsr.io/@nodef/extra-string/doc/~/splice [reverse]: https://jsr.io/@nodef/extra-string/doc/~/reverse [sort]: https://jsr.io/@nodef/extra-string/doc/~/sort [filter]: https://jsr.io/@nodef/extra-string/doc/~/filter [spaces]: https://jsr.io/@nodef/extra-string/doc/~/spaces [is]: https://jsr.io/@nodef/extra-string/doc/~/is [isEmpty]: https://jsr.io/@nodef/extra-string/doc/~/isEmpty [isCharacter]: https://jsr.io/@nodef/extra-string/doc/~/isCharacter [index]: https://jsr.io/@nodef/extra-string/doc/~/index [indexRange]: https://jsr.io/@nodef/extra-string/doc/~/indexRange [codePointRange]: https://jsr.io/@nodef/extra-string/doc/~/codePointRange [compare]: https://jsr.io/@nodef/extra-string/doc/~/compare [isEqual]: https://jsr.io/@nodef/extra-string/doc/~/isEqual [get]: https://jsr.io/@nodef/extra-string/doc/~/get [getAll]: https://jsr.io/@nodef/extra-string/doc/~/getAll [set]: https://jsr.io/@nodef/extra-string/doc/~/set [begin]: https://jsr.io/@nodef/extra-string/doc/~/begin [middle]: https://jsr.io/@nodef/extra-string/doc/~/middle [end]: https://jsr.io/@nodef/extra-string/doc/~/end [longestCommonInfix]: https://jsr.io/@nodef/extra-string/doc/~/longestCommonInfix [longestCommonPrefix]: https://jsr.io/@nodef/extra-string/doc/~/longestCommonPrefix [longestCommonSuffix]: https://jsr.io/@nodef/extra-string/doc/~/longestCommonSuffix [longestUncommonInfixes]: https://jsr.io/@nodef/extra-string/doc/~/longestUncommonInfixes [toBaseline]: https://jsr.io/@nodef/extra-string/doc/~/toBaseline [toSuperscript]: https://jsr.io/@nodef/extra-string/doc/~/toSuperscript [toSubscript]: https://jsr.io/@nodef/extra-string/doc/~/toSubscript [toKebabCase]: https://jsr.io/@nodef/extra-string/doc/~/toKebabCase [toSnakeCase]: https://jsr.io/@nodef/extra-string/doc/~/toSnakeCase [toCamelCase]: https://jsr.io/@nodef/extra-string/doc/~/toCamelCase [toPascalCase]: https://jsr.io/@nodef/extra-string/doc/~/toPascalCase [toSlugCase]: https://jsr.io/@nodef/extra-string/doc/~/toSlugCase [toWords]: https://jsr.io/@nodef/extra-string/doc/~/toWords [ngrams]: https://jsr.io/@nodef/extra-string/doc/~/ngrams [uniqueNgrams]: https://jsr.io/@nodef/extra-string/doc/~/uniqueNgrams [countNgrams]: https://jsr.io/@nodef/extra-string/doc/~/countNgrams [countUniqueNgrams]: https://jsr.io/@nodef/extra-string/doc/~/countUniqueNgrams [countEachNgram]: https://jsr.io/@nodef/extra-string/doc/~/countEachNgram [matchingNgrams]: https://jsr.io/@nodef/extra-string/doc/~/matchingNgrams [uniqueMatchingNgrams]: https://jsr.io/@nodef/extra-string/doc/~/uniqueMatchingNgrams [countMatchingNgrams]: https://jsr.io/@nodef/extra-string/doc/~/countMatchingNgrams [countEachMatchingNgram]: https://jsr.io/@nodef/extra-string/doc/~/countEachMatchingNgram [countUniqueMatchingNgrams]: https://jsr.io/@nodef/extra-string/doc/~/countUniqueMatchingNgrams [euclideanDistance]: https://jsr.io/@nodef/extra-string/doc/~/euclideanDistance [hammingDistance]: https://jsr.io/@nodef/extra-string/doc/~/hammingDistance [jaccardIndex]: https://jsr.io/@nodef/extra-string/doc/~/jaccardIndex [jaccardDistance]: https://jsr.io/@nodef/extra-string/doc/~/jaccardDistance [sorensenDiceIndex]: https://jsr.io/@nodef/extra-string/doc/~/sorensenDiceIndex [sorensenDiceDistance]: https://jsr.io/@nodef/extra-string/doc/~/sorensenDiceDistance [tverskyIndex]: https://jsr.io/@nodef/extra-string/doc/~/tverskyIndex [tverskyDistance]: https://jsr.io/@nodef/extra-string/doc/~/tverskyDistance [jaroSimilarity]: https://jsr.io/@nodef/extra-string/doc/~/jaroSimilarity [jaroDistance]: https://jsr.io/@nodef/extra-string/doc/~/jaroDistance [jaroWinklerSimilarity]: https://jsr.io/@nodef/extra-string/doc/~/jaroWinklerSimilarity [jaroWinklerDistance]: https://jsr.io/@nodef/extra-string/doc/~/jaroWinklerDistance [levenshteinDistance]: https://jsr.io/@nodef/extra-string/doc/~/levenshteinDistance [damerauLevenshteinDistance]: https://jsr.io/@nodef/extra-string/doc/~/damerauLevenshteinDistance