如何在bootstrap中计算推/拉顺序单元？(How I can calculate push/pull order cell in bootstrap?)

 这只是一个猜测，但这是我认为发生的事情： 
 
 
 
 当您宣布Superhero ，您声明name和power应该具有相同的生命周期。 
 
 
 r的类型被推断为&String （或者可能是&str ，点是r是引用）。 在词汇生命周期中， r必须存活到声明它的块的末尾，所以直到第14行。 
 
 
 因为你影响了hero.name到r ， hero.name应该至少与r一样长，因此hero.name应该存在直到第14行。 
 
 
 由于hero.name和hero.power应该具有相同的结构声明生命周期，因此hero.power也应该存在直到第14行。 
 
 
 由于hero.power借用了p ， p应该一直存在到第14行，但它只能存在到声明它的块的末尾（第13行）。 
 
 
 它适用于非词汇生命周期的原因是因为编译器注意到你没有在第12行之后使用r ，因此能够相应地缩短生命周期。 请注意， 如果在第13行的右括号后使用r ， 它甚至不能用于nll 。 

This is only a guess, but here is what I think happens:
 
 
 
When you declared Superhero, you stated that name and power should have the same lifetime.
 
 
The type for r is inferred as &String (or maybe &str, the point is that r is a reference). With lexical lifetimes, r must live until the end of the block in which it is declared, so until line 14.
 
 
Since you affect hero.name to r, hero.name should live at least as long as r, therefore hero.name should live until line 14.
 
 
Since hero.name and hero.power should have the same lifetime per the struct declaration, hero.power should also live until line 14.
 
 
Since hero.power borrows p, p should live until line 14, but it only lives until the end of the block in which it is declared (line 13).
 
 
The reason it works with non-lexical lifetimes is because the compiler notices that you don't use r after line 12 and is therefore able to shorten the lifetimes accordingly. Note that it doesn't work even with nll if you use r after the closing brace of line 13.