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From: Bonita Montero <Bonita.Montero@gmail.com>
Newsgroups: comp.lang.c
Subject: Re: C23 auto x C++ auto.
Date: Sun, 26 May 2024 16:22:28 +0200
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Am 26.05.2024 um 15:49 schrieb Thiago Adams:
> I think most people is not aware of this:
> 
>  From 3096 C23 draft
> 
> "
> 6.7.9 Type inference
> ...
>   2 For such a declaration that is the definition of an object the init- 
>    declarator shall have the form
> 
>     direct-declarator = assignment-expression
> "
> 
> Basically "direct-declarator" differs from "declarator" because it does 
> not contains pointer.
> 
> Then the type inference using auto and pointer is something undefined in 
> C23.
> 
> struct node{
>      struct node * next;
> 
> };
> int main(){
>     struct node node = {};
>     auto * p = node.next;
> }
> 
> <source>:7:4: error: 'auto' requires a plain identifier, possibly with 
> attributes, as declarator
>      7 |    auto * p = node.next;
>        |    ^~~~
> 
> This differs from C++.
> 
> 

I don't know what type inference in C is good for since the type names
in C are usually short. If I have short typenames in C++ I don't use
type inference. Type-inference makes sense to make such things shorter
     typename map<string, string>::const_iterator it = map.cbegin();
This doesn't happen in C.