String

String transformation and formatting. Import from @pivanov/utils/string or @pivanov/utils.

Case conversion

camelCase(str)

camelCase('foo-bar');        // 'fooBar'
camelCase('FOO_BAR');        // 'fooBar'
camelCase('Foo Bar Baz');    // 'fooBarBaz'

pascalCase(str)

pascalCase('foo-bar');       // 'FooBar'
pascalCase('foo123bar');     // 'Foo123Bar'
pascalCase('FOO_BAR_BAZ');   // 'FooBarBaz'

kebabCase(str)

kebabCase('fooBar');         // 'foo-bar'
kebabCase('XMLHttpRequest'); // 'xml-http-request'
kebabCase('é è à ù');        // 'e-e-a-u'

snakeCase(str)

snakeCase('fooBar');         // 'foo_bar'
snakeCase('XMLHttpRequest'); // 'xml_http_request'

titleCase(str)

titleCase('hello world');    // 'Hello World'
titleCase('foo-bar_baz');    // 'Foo Bar Baz'

null / undefined handling

kebabCase and snakeCase pass null / undefined through unchanged (legacy behavior). The other converters throw.

Capitalization

capitalize<S>(str) · uncapitalize<S>(str)

Literal-type preserving. Use these when you care about TypeScript inferring the exact capitalized string.

const s: 'hello' = 'hello';
const cap = capitalize(s); // type: 'Hello'

capitalizeFirstLetter(str)

Runtime-only version that accepts any string.

Slugs

slugify(str)

More aggressive than kebabCase - strips all non-ASCII-word characters. Good for URL slugs.

slugify('Hello World!');        // 'hello-world'
slugify('Über Café');            // 'uber-cafe'
slugify('Complex@#$%^&* String'); // 'complex-string'
slugify('한글');                  // ''   (non-Latin dropped)

Truncation

truncate(str, maxLength, ellipsis?)

Truncates to maxLength characters, appending ellipsis (default …). The ellipsis counts toward the final length.

truncate('Hello, world!', 8);         // 'Hello, …'
truncate('Hello, world!', 8, '...');  // 'Hello...'
truncate('Short', 20);                // 'Short'

Escaping

escapeHtml(str)

Escapes & < > " ' for safe interpolation into HTML.

escapeHtml('<script>alert("1")</script>');
// '&lt;script&gt;alert(&quot;1&quot;)&lt;/script&gt;'

escapeRegExp(str)

Escapes regex metacharacters so a string can be embedded as a literal match.

const needle = 'a.b*c';
const re = new RegExp(escapeRegExp(needle));
re.test('a.b*c'); // true

Splitting

words(str)

Splits on whitespace, dashes, and underscores. Filters empties.

words('hello_world-foo bar'); // ['hello', 'world', 'foo', 'bar']

lines(str)

Splits on any line break style (\r\n, \n, \r).

lines('a\nb\r\nc\rd'); // ['a', 'b', 'c', 'd']

Choosing the right function

Need	Use
Variable names	camelCase
Class / component names	pascalCase
CSS classes, HTML attrs	kebabCase
Python/Rust-style identifiers	snakeCase
UI headings	titleCase
URL slug	slugify
Safe HTML interpolation	escapeHtml
Build a regex from user input	escapeRegExp