[Top][All Lists]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Behavior of #!optional

From: Evan Hanson
Subject: Re: Behavior of #!optional
Date: Tue, 3 Mar 2020 21:21:36 +1300

Hi Théo,

I don't know whether there are any firm guarantees about that behaviour,
but functionally it's safe to rely on, yes. That idiom you mentioned is
pretty handy, I use it myself sometimes.

Under the hood, #!optional arguments are expanded in a let*-style
binding form (as opposed to a "normal" let binding, where they wouldn't
see one another), so later values can refer to earlier ones.



reply via email to

[Prev in Thread] Current Thread [Next in Thread]