🎉 initiate project *astro_rewrite*

node_modules/mdast-util-to-markdown/lib/util/check-emphasis.js

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+/**
+ * @typedef {import('../types.js').State} State
+ * @typedef {import('../types.js').Options} Options
+ */
+
+/**
+ * @param {State} state
+ * @returns {Exclude<Options['emphasis'], null | undefined>}
+ */
+export function checkEmphasis(state) {
+  const marker = state.options.emphasis || '*'
+
+  if (marker !== '*' && marker !== '_') {
+    throw new Error(
+      'Cannot serialize emphasis with `' +
+        marker +
+        '` for `options.emphasis`, expected `*`, or `_`'
+    )
+  }
+
+  return marker
+}