rticleBySlug</span><span class="token punctuation">(</span>dao <span class="token operator">*</span>daos<span class="token punctuation">.</span>Dao<span class="token punctuation">,</span> slug <span class="token builtin">string</span><span class="token punctuation">)</span> <span class="token punctuation">(</span><span class="token operator">*</span>Article<span class="token punctuation">,</span> <span class="token builtin">error</span><span class="token punctuation">)</span> <span class="token punctuation"