Function parseLanguage

http/_negotiation/language.ts:42–71

(
  str: string,
  i: number,
)

const SIMPLE_LANGUAGE_REGEXP = /^\s*([^\s\-;]+)(?:-([^\s;]+))?\s*(?:;(.*))?$/;

function parseLanguage(
  str: string,
  i: number,
): LanguageSpecificity | undefined {
  const match = SIMPLE_LANGUAGE_REGEXP.exec(str);
  if (!match) {
    return undefined;
  }

  const [, prefix, suffix] = match;
  if (!prefix) {
    return undefined;
  }

  const full = suffix !== undefined ? `${prefix}-${suffix}` : prefix;

  let q = 1;
  if (match[3]) {
    const params = match[3].split(";");
    for (const param of params) {
      const [key, value] = param.trim().split("=");
      if (key === "q" && value) {
        q = parseFloat(value);
        break;
      }
    }
  }

  return { prefix, suffix, full, i, o: undefined, q, s: undefined };
}

function parseAcceptLanguage(accept: string): LanguageSpecificity[] {
  const accepts = accept.split(",");