Re: understanding code
- To: mathgroup at smc.vnet.net
- Subject: [mg114221] Re: understanding code
- From: Bill Rowe <readnews at sbcglobal.net>
- Date: Sat, 27 Nov 2010 03:38:43 -0500 (EST)
On 11/26/10 at 5:49 PM, lshifr at gmail.com (Leonid Shifrin) wrote: >PreIncrement must have been implemented on the higher level, using >Set Your example makes sense. >In any case, there seem to be no additional restrictions imposed by >PreIncrement on an expression being incremented, as compared to >those of Set (that it must be an L - value). Particularly, indexed >variables like i[1] are ok. I would say that using i[1] to be an indexed variable is something that needs to be done with care. When a value is assigned such as i[1]=0, i now has a down value. But for an ordinary variable x doing x = 1 does not create a down value. This difference means using i[1] to be and indexed variable will result in different behavior than using an ordinary variable in some cases.