在2022年4月25日星期一 UTC+8 21:26:30<Stephan Merz> 写道：
Hello,
> On 25 Apr 2022, at 04:26, 宏黄 <wpk...@xxxxxxxxx> wrote:
>
> Hi all.
> I'm reading the TLA+ hyperbook ，And I met some questions.
> In Chapter 17 Temporal Logic Question 17.5
> How to prove []p=>p' is not equivalent to any legal TLA+ formula.
hint: all temporal formulas of TLA+ are insensitive to inserting or removing stuttering steps.
> and in Chapter 17.4.1 lead to
> How to understand F~>false,i think it is nerver true,when F is true,false do not become true
F ~> FALSE asserts that if F ever becomes true, then FALSE must be true eventually. Since the latter is impossible, the formula expresses that F can never become true. You would normally write this as []~F, but the formulation using leads-to is more convenient in the context of reasoning about leads-to properties.
Hope this helps,
Stephan