Sorry, I love Rust but I can’t really agree with you here. They only showed a macro_rules!definition, which is definitely rust syntax. Lifetime annotations are relatively common.
I will concede that loop labels are incredibly rare though.
I guess I see what you mean if we want to get very technical about what a syntax extension is. But I think for the purpose of this discussion, it’s reasonable to think of macro_rules! as a part of the Rust language. Practically speaking, it is syntax provided by the language team, not just users of the language who are free to extend the syntax by usingmacro_rules! to do so.
Loop labels are rare, but they lead to much simpler/clearer code when you need them. Consider how you would implement this kind of loop in a language without loop variables:
'outer: while (...) {
'inner: while (...) {
if (...) {
// this breaks out of the outer loop, not just the inner loopbreak'outer;
}
}
// some code here
}
In C/C++ you’d need to do something like
bool condition = false;
while (...) {
while (...) {
if (...) {
condition = true;
break;
}
}
if (condition) {
break;
}
// some code here
}
Personally, I wouldn’t call it ugly, either, but that’s mostly a matter of taste
Well, you’d typically put the loops into a function and then do an explicit return to jump out of there. I believe, there’s some use-cases where this isn’t possible, which is why I’m cool with loop labels existing, but I’ve been coding Rust for seven years and have not needed them once…
You used macro_rules, which is not common at all. Most rust files don’t contain any macro definition.
This code doesn’t even compile. There is a random function definition, and then there are loose statements not inside any code block.
The loop is also annotated, which is not common at all, and when loops are annotated it’s a blessing for readability. Additionally, the loop (+annotation) is indented for some reason.
And the loop doesn’t contain any codeblock. Just an opening bracket.
Also, the function definition contains a lifetime annotation. While they are not uncommon, I wouldn’t say the average rust function contains them. Of course their frequency changes a lot depending on context, but in my experience most functions I write/read don’t have lifetime annotations at all.
Yes, what you wrote somewhat resembles rust. But it is in no way average rust code.
Sorry, I love Rust but I can’t really agree with you here. They only showed a
macro_rules!definition, which is definitely rust syntax. Lifetime annotations are relatively common.I will concede that loop labels are incredibly rare though.
https://fprijate.github.io/tlborm/mbe-macro-rules.html#%3A~%3Atext=macro_rules!+With%2Cfollowing+form%3A
I guess I see what you mean if we want to get very technical about what a syntax extension is. But I think for the purpose of this discussion, it’s reasonable to think of
macro_rules!as a part of the Rust language. Practically speaking, it is syntax provided by the language team, not just users of the language who are free to extend the syntax by usingmacro_rules!to do so.Loop labels are rare, but they lead to much simpler/clearer code when you need them. Consider how you would implement this kind of loop in a language without loop variables:
'outer: while (...) { 'inner: while (...) { if (...) { // this breaks out of the outer loop, not just the inner loop break 'outer; } } // some code here }In C/C++ you’d need to do something like
bool condition = false; while (...) { while (...) { if (...) { condition = true; break; } } if (condition) { break; } // some code here }Personally, I wouldn’t call it ugly, either, but that’s mostly a matter of taste
Well, you’d typically put the loops into a function and then do an explicit
returnto jump out of there. I believe, there’s some use-cases where this isn’t possible, which is why I’m cool with loop labels existing, but I’ve been coding Rust for seven years and have not needed them once…What language are they then? They’re not Python, JS, <insert any other language here>
You used macro_rules, which is not common at all. Most rust files don’t contain any macro definition.
This code doesn’t even compile. There is a random function definition, and then there are loose statements not inside any code block.
The loop is also annotated, which is not common at all, and when loops are annotated it’s a blessing for readability. Additionally, the loop (+annotation) is indented for some reason.
And the loop doesn’t contain any codeblock. Just an opening bracket.
Also, the function definition contains a lifetime annotation. While they are not uncommon, I wouldn’t say the average rust function contains them. Of course their frequency changes a lot depending on context, but in my experience most functions I write/read don’t have lifetime annotations at all.
Yes, what you wrote somewhat resembles rust. But it is in no way average rust code.