Comment by anonym29 | Hacker News Reader

Comment by anonym29 | Hacker News Reader

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Where's the language spec? The reference is nice but it's not a formal specification.

So much undefined behavior - more than C! /s

Edited to reflect sarcasm as rustaceans apparently can't infer it.

In my understanding it would be hard to make the case that Rust actually has more undefined behavior than C -- most kinds of undefined behavior in C have been carefully avoided in Rust, although, yes, there is no piece of paper ratified by a bunch of national technology institutes that describes Rust.

See also this recent blog post:

https://blog.m-ou.se/rust-standard/

While the rust community might not believe their language needs a specification, some of their would-be customers have business requirements surrounding a specification that cannot be fulfilled with a reference.

edit: clarity

A standard or a specification? Anyway, hopefully Ferrocene will be able to provide those folks what they need.

https://ferrous-systems.com/ferrocene/

Thank you for catching this mistake on my part, fixed.

Can you explain what the difference is between a standard and a reference?

See edit

Of course you'd expect a formal specification to include details on what the fundamental data types actually are - C11 can't be nailed down on what char is, it defines it as a type large enough to store a member of the implementation-defined basic character set with implementation defined signedness. Which means you could have a valid implementation with anything from a 4-bit unsigned char to a 256 bit or larger signed char

> Which means you could have a valid implementation with anything from a 4-bit unsigned char to a 256 bit or larger signed char

This is not quite accurate; there is no upper limit to the number of bits in a char (except for INTMAX_MAX, perhaps), but it cannot have any fewer than 8 bits, including a possible sign bit.

All the C types have had minimum allowed ranges going back to ANSI C.

For 'char', it must at least support the range 0 to 127 (and in addition, it must have the same range as either 'unsigned char' or 'signed char').

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