<p>reducer폴더의 post.js에서</p>
<div style="color: #d4d4d4; background-color: #1e1e1e; font-family: Consolas, 'Courier New', monospace; font-size: 14px; line-height: 19px; white-space: pre;">
<div>&nbsp;<span style="color: #c586c0;">case</span>&nbsp;<span style="color: #4fc1ff;">LOAD_POSTS_SUCCESS</span>:</div>
<div>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="color: #9cdcfe;">draft</span>.<span style="color: #9cdcfe;">loadPostsLoading</span>&nbsp;=&nbsp;<span style="color: #569cd6;">false</span>;</div>
<div>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="color: #9cdcfe;">draft</span>.<span style="color: #9cdcfe;">loadPostsDone</span>&nbsp;=&nbsp;<span style="color: #569cd6;">true</span>;</div>
<div>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="color: #9cdcfe;">draft</span>.<span style="color: #9cdcfe;">mainPosts</span>&nbsp;=&nbsp;<span style="color: #9cdcfe;">draft</span>.<span style="color: #9cdcfe;">mainPosts</span>.<span style="color: #dcdcaa;">concat</span>(<span style="color: #9cdcfe;">action</span>.<span style="color: #9cdcfe;">data</span>);</div>
<div>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="color: #9cdcfe;">draft</span>.<span style="color: #9cdcfe;">hasMorePosts</span>&nbsp;=&nbsp;<span style="color: #9cdcfe;">action</span>.<span style="color: #9cdcfe;">data</span>.<span style="color: #9cdcfe;">length</span>&nbsp;===&nbsp;<span style="color: #b5cea8;">10</span>;</div>
<div>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="color: #c586c0;">break</span>;</div>
</div>
<p>이 코드를</p>
<div style="color: #d4d4d4; background-color: #1e1e1e; font-family: Consolas, 'Courier New', monospace; font-size: 14px; line-height: 19px; white-space: pre;">
<div><span style="color: #c586c0;">case</span>&nbsp;<span style="color: #4fc1ff;">LOAD_POSTS_SUCCESS</span>:</div>
<div>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="color: #9cdcfe;">draft</span>.<span style="color: #9cdcfe;">loadPostsLoading</span>&nbsp;=&nbsp;<span style="color: #569cd6;">false</span>;</div>
<div>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="color: #9cdcfe;">draft</span>.<span style="color: #9cdcfe;">loadPostsDone</span>&nbsp;=&nbsp;<span style="color: #569cd6;">true</span>;</div>
<div>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="color: #9cdcfe;">draft</span>.<span style="color: #9cdcfe;">mainPosts</span>&nbsp;=&nbsp;<span style="color: #9cdcfe;">action</span>.<span style="color: #9cdcfe;">data</span>;</div>
<div>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="color: #9cdcfe;">draft</span>.<span style="color: #9cdcfe;">hasMorePosts</span>&nbsp;=&nbsp;<span style="color: #9cdcfe;">action</span>.<span style="color: #9cdcfe;">data</span>.<span style="color: #9cdcfe;">length</span>&nbsp;===&nbsp;<span style="color: #b5cea8;">10</span>;</div>
<div>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<span style="color: #c586c0;">break</span>;</div>
</div>
<p>이와같이 바꿔봤는데 똑같이 작동하더라구요?</p>
<p>draft.mainPosts = draft.mainPosts.concat(action.data);</p>
<p>draft.mainPosts = action.data;</p>
<p>이 둘의 차이점이 무엇인지 궁금합니다. 첫번째것은 mainPosts에 콘캣해서 배열을 합치는 것이고</p>
<p>두번째에서 action.data도 같은 기능을 하는것 같은데 무엇이 차이일까요?</p>

<p>첫 번째처럼 쓰셔야 나중에 데이터를 추가로 불러올 때 기존 데이터와 합쳐집니다. 두 번째처럼 하시면 데이터를 추가로 불러올 때 기존 데이터가 사라집니다.</p>

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