What is the use of '&' symbol ?

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sky_coder
Posts: 1
Joined: Fri Nov 30, 2012 11:28 pm

What is the use of '&' symbol ?

Post by sky_coder » Fri Nov 30, 2012 11:33 pm

I have been wondering what is the use of '&' symbol.

For example ...

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(defun abc ( attr goal &opt prior &aux (tree nil) ) 
...
 )

nuntius
Posts: 538
Joined: Sat Aug 09, 2008 10:44 am
Location: Newton, MA

Re: What is the use of '&' symbol ?

Post by nuntius » Wed Dec 19, 2012 12:20 am

Sorry for not replying earlier. In Lisp, "&word" is not the symbol "&" followed by "word", it is actually a single symbol name. The "&" has no special significance to the compiler; it is just something that stands out to the human reader.

Here's a list of common naming conventions. http://www.cliki.net/naming%20conventions

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