Improve code readability

src/api_data/comment_api.rs

@@ -49,7 +49,7 @@ impl CommentAPI {
         Ok(c_api)
     }
 
-    pub fn for_list(l: &Vec<Comment>, curr_user_id: &Option<UserID>) -> ResultBoxError<Vec<CommentAPI>> {
+    pub fn for_list(l: &[Comment], curr_user_id: &Option<UserID>) -> ResultBoxError<Vec<CommentAPI>> {
         l.iter().map(|c| Self::new(c, curr_user_id)).collect()
     }
 }

src/api_data/post_api.rs

@@ -114,7 +114,7 @@ impl PostAPI {
             PostKind::POST_KIND_COUNTDOWN(time_end) => post.time_end = Some(*time_end),
 
             PostKind::POST_KIND_SURVEY =>
-                post.data_survey = Some(SurveyAPI::new(&survey_helper::get_info(p.id)?, user.clone())?),
+                post.data_survey = Some(SurveyAPI::new(&survey_helper::get_info(p.id)?, *user)?),
 
             PostKind::POST_KIND_YOUTUBE(id) => {
                 post.file_path = Some(id.clone());
@@ -130,7 +130,7 @@ impl PostAPI {
     }
 
     /// Turn a list of posts into an API entry
-    pub fn for_list(l: &Vec<Post>, user_id: Option<UserID>) -> ResultBoxError<Vec<PostAPI>> {
+    pub fn for_list(l: &[Post], user_id: Option<UserID>) -> ResultBoxError<Vec<PostAPI>> {
         l.iter().map(|p| Self::new(p, &user_id)).collect()
     }
 }

src/api_data/survey_choice_api.rs

@@ -25,7 +25,7 @@ impl SurveyChoiceAPI {
         }
     }
 
-    pub fn for_list(c: &Vec<SurveyChoice>) -> HashMap<u64, SurveyChoiceAPI> {
+    pub fn for_list(c: &[SurveyChoice]) -> HashMap<u64, SurveyChoiceAPI> {
         let mut map = HashMap::with_capacity(c.len());
         c.iter().for_each(|c| { map.insert(c.id, Self::new(c)); });
         map