Function fn

packages/markmap-lib/src/plugins/katex/index.browser.ts:41–45

(tokens, idx)

      md.use(katexPlugin);
      ['math_block', 'math_inline'].forEach((key) => {
        const fn: MarkdownIt.Renderer.RenderRule = (tokens, idx) => {
          enableFeature();
          const result = renderKatex(tokens[idx].content, !!tokens[idx].block);
          return result;
        };
        md.renderer.rules[key] = fn;
      });
    });