import type { FormattedPrimitiveTypeCreator } from '../types.js';
/**
 * Checks whether a string is a valid custom element name.
 *
 * > PotentialCustomElementName ::=
 * >   [a-z] (PCENChar)* '-' (PCENChar)*
 * > PCENChar ::=
 * >   "-" | "." | [0-9] | "_" | [a-z] | #xB7 | [#xC0-#xD6] | [#xD8-#xF6] | [#xF8-#x37D] |
 * >   [#x37F-#x1FFF] | [#x200C-#x200D] | [#x203F-#x2040] | [#x2070-#x218F] | [#x2C00-#x2FEF] | [#x3001-#xD7FF] | [#xF900-#xFDCF] | [#xFDF0-#xFFFD] | [#x10000-#xEFFFF]
 * > This uses the EBNF notation from the XML specification. [XML]
 *
 * > They start with an ASCII lower alpha, ensuring that the HTML parser will treat them as tags instead of as text.
 *
 * > - name must match the [PotentialCustomElementName](https://html.spec.whatwg.org/multipage/custom-elements.html#prod-potentialcustomelementname) production
 * > - name must not be any of the following:
 * >   - `<annotation-xml>`
 * >   - `<color-profile>`
 * >   - `<font-face>`
 * >   - `<font-face-src>`
 * >   - `<font-face-uri>`
 * >   - `<font-face-format>`
 * >   - `<font-face-name>`
 * >   - `<missing-glyph>`
 *
 * @see https://html.spec.whatwg.org/multipage/custom-elements.html#valid-custom-element-name
 */
export declare const isCustomElementName: FormattedPrimitiveTypeCreator;