Re: MyPrependTo
- To: mathgroup at smc.vnet.net
- Subject: [mg15988] Re: MyPrependTo
- From: Dan Truong <dtruong at irisa.fr>
- Date: Fri, 19 Feb 1999 03:27:06 -0500
- Organization: Irisa, Rennes (FR)
- References: <7ag26u$ag9@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
> In[2]:= > push[someStack_, elt_] := (someStack = Prepend[someStack, elt];) Is it legal in Mathematica to assign a function parameter? I think not, because they are avaluated before going in the function body (ie, parameters are passed by value, not by reference or pointers) The solution is to use a golbal stack parameter, or to use Return[] Push[...] := ( Return[Prepend[...]]); e = Push[e,1]; BTW: does anyone know how to pass a pointer to an object so it can be modified and returned? HoldFirst etc. do not do that. -- Dan N. Truong, IRISA, Campus de Beaulieu, 35042 Rennes Cedex, FRANCE tel:(+33)2 99 84 25 39 fax:(+33)2 99 84 25 28 mailto:dtruong at irisa.fr http://www.irisa.fr/caps/PEOPLE/Dan gsm:06 14 78 06 95 -> http://www.sfr.fr/html/annexes/sms/sendsms.html