javascript - 为什么 jshint 不能将赋值识别为表达式？

Question

我需要如何修改这些行以使 jshint 满意？

赋值是一个表达式。为什么 jshint 不明白这一点？很明显，翻译是这样的。

Line 572: while(bookmark_element=bookmark_list[iterator++])

Expected a conditional expression and instead saw an assignment.


Line 582: while(bookmark_element=bookmark_list[iterator++])

Expected a conditional expression and instead saw an assignment.


Line 623: while(element_iterator=element_iterator.nextSibling)

Expected a conditional expression and instead saw an assignment.

Answer 1

如果您真的想听 JSHint，请通过以下方式将表达式转换为 bool 值:

while (!!(bookmark_element=bookmark_list[iterator++]))

! means: Something that evaluates to true is converted to false,
         something that evaluates to false is converted to true.

所以， !!意思是:将某些东西转换为条件表示。