diff --git a/redesign/error.nim b/redesign/error.nim
index fb96758..af04e73 100644
--- a/redesign/error.nim
+++ b/redesign/error.nim
@@ -40,4 +40,23 @@ when defined(js):
           let e = error.get()
           if (e.errorFields.len == 1 and e.errorFields[0] == name) or isLast:
             p(class="form-input-hint"):
-              text e.message
\ No newline at end of file
+              text e.message
+
+  template postFinished*(onSuccess: untyped): untyped =
+    state.loading = false
+    let status = httpStatus.HttpCode
+    if status == Http200:
+      onSuccess
+    else:
+      # TODO: Karax should pass the content-type...
+      try:
+        let parsed = parseJson($response)
+        let error = to(parsed, PostError)
+
+        state.error = some(error)
+      except:
+        kout(getCurrentExceptionMsg().cstring)
+        state.error = some(PostError(
+          errorFields: @[],
+          message: "Unknown error occurred."
+        ))
\ No newline at end of file
diff --git a/redesign/login.nim b/redesign/login.nim
index 94a9228..6485906 100644
--- a/redesign/login.nim
+++ b/redesign/login.nim
@@ -17,24 +17,9 @@ when defined(js):
       error: Option[PostError]
 
   proc onLogInPost(httpStatus: int, response: kstring, state: LoginModal) =
-    state.loading = false
-    let status = httpStatus.HttpCode
-    if status == Http200:
+    postFinished:
       state.shown = false
       state.onLogIn()
-    else:
-      # TODO: Karax should pass the content-type...
-      try:
-        let parsed = parseJson($response)
-        let error = to(parsed, PostError)
-
-        state.error = some(error)
-      except:
-        kout(getCurrentExceptionMsg().cstring)
-        state.error = some(PostError(
-          errorFields: @[],
-          message: "Unknown error occurred."
-        ))
 
   proc onLogInClick(ev: Event, n: VNode, state: LoginModal) =
     state.loading = true
diff --git a/redesign/replybox.nim b/redesign/replybox.nim
index b92dc88..04852f2 100644
--- a/redesign/replybox.nim
+++ b/redesign/replybox.nim
@@ -40,24 +40,9 @@ when defined(js):
     state.shown = true
 
   proc onPreviewPost(httpStatus: int, response: kstring, state: ReplyBox) =
-    state.loading = false
-    let status = httpStatus.HttpCode
-    if status == Http200:
+    postFinished:
       kout(response)
       state.rendering = some[kstring](response)
-    else:
-      # TODO: login has similar code, abstract this.
-      try:
-        let parsed = parseJson($response)
-        let error = to(parsed, PostError)
-
-        state.error = some(error)
-      except:
-        kout(getCurrentExceptionMsg().cstring)
-        state.error = some(PostError(
-          errorFields: @[],
-          message: "Unknown error occurred."
-        ))
 
   proc onPreviewClick(e: Event, n: VNode, state: ReplyBox) =
     state.preview = true
@@ -71,25 +56,10 @@ when defined(js):
              (s: int, r: kstring) => onPreviewPost(s, r, state))
 
   proc onReplyPost(httpStatus: int, response: kstring, state: ReplyBox) =
-    state.loading = false
-    let status = httpStatus.HttpCode
-    if status == Http200:
+    postFinished:
       state.text = ""
       state.shown = false
       state.onPost(parseJson($response).getInt())
-    else:
-      # TODO: login has similar code, abstract this.
-      try:
-        let parsed = parseJson($response)
-        let error = to(parsed, PostError)
-
-        state.error = some(error)
-      except:
-        kout(getCurrentExceptionMsg().cstring)
-        state.error = some(PostError(
-          errorFields: @[],
-          message: "Unknown error occurred."
-        ))
 
   proc onReplyClick(e: Event, n: VNode, state: ReplyBox,
                     thread: Thread, replyingTo: Option[Post]) =