Immutable fields

[Leandro Lucarella]

Jonathan M Davis, el  2 de noviembre a las 20:02 me escribiste:
> On Tuesday 02 November 2010 19:24:29 bearophile wrote:
> > Jonathan M Davis:
> > > Why would it really matter though?
> > 
> > I guess you have not followed my link with more explanations, right? :-)
> > 
> > Bye,
> > bearophile
> 
> I don't really get what you're doing there or what the problem is. You cast one 
> struct to another struct and it retained the same value for x. That seems 
> logical enough. You're just viewing that chunk of memory as a new type. You 
> didn't actually change what's there. My first reaction to seeing that sort of 
> cast though is that it's a bad idea anyway, though I guess that whether an 
> immutable variable has storage could affect the result in such a case. Generally 
> though, I would have argued that if you weren't going to set the variable with 
> the constructor, it should probably be an enum anyway.

I don't think it's a good idea to optimize out a struct member, as
structs are often used to represent memory layouts when interacting with
low level stuff (or not so low-level, like reading and writing a packet
from the network). It seems pretty silly to have to avoid using
immutable in those cases just to let the compiler "please, don't remove
store from this struct".

-- 
Leandro Lucarella (AKA luca)                     http://llucax.com.ar/
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