code: function convertPlaceholders (value) {
        // Probably AST nodes.
        if (typeof value !== 'string') {
          return [value]
        }
  
        const items = value.split(placeholderRe)
        let placeholder = true
        return items.map((item) => {
          placeholder = !placeholder
          return placeholder ? expressions[item] : t.stringLiteral(item)
        })
      }
docs: Convert placeholders used in the template string back to the AST nodes
  they reference.