I don't get what you mean. Every packet has a fixed header of 2 bytes. I though I should implement a fixed_header parser and other parser to parse the packet? But I don't get what the proper way of doing so. This is what I've started
So have a different parser for each fixed_header of each packet?
Instead of a header followed by a type, it's one alternate type after another each beginning with a constant u8.
at the end, an error is generated when nothing looked like a valid type.
Alternatively you can parse the header and then do a
match kind { ... }, choosing the parser based on the kind and making an error manually if the kind is not a known one.
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IMHO, being able to use just normal Rust code when it's more clear than the Nom-native way is a feature of modern
nom versions, not a bug.
One thing I'm missing in the functional
nom is something like the legacy do_parse macro... I wonder whether it could be a good idea to bring it back.
You wouldn't get an error from be_u8, you'd just get some number outside the valid range.
Not for
be_u8, to avoid conflating "an unknown variant" with "a known variant rejected due to an internal error"
I don't know much about nom's errors, but I feel them being context aware would be critical... I.E. you'd be able to tell the type u8 was where the matching failed.
The problem is that
alt, IIRC, would just tell you that "at position 0 all 15 possible branches failed" without telling you whether any one went beyond the first byte.
Hi all, so I'm a bit of a rust noob, and I'm really having a hard time understanding the lifetimes here https://play.rust-lang.org/?version=stable&mode=debug&edition=2015&gist=c2260098b1b7199477cf4f27b44dfd14. Sorry for not having a detailed explanation of my problem. I'm not sure what else more to say. Trying to read a file then parse that, but for some reason I'm getting lifetime errors when passing a &[u8] of a vec<u8>
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I can paste the error when I’m at my computer again, but I remember it being E0515
It does appear to be relating to ? And using a boxed dyn Error. Changed to use unwrap and it’s fine
It was just a contrived example from code at work so I didn’t have to think about errors since I’m just hacking around right now lol
But yeah I agree
Also from experience, I tend to have better luck when I use enums in place of dyn.
Thanks for pointing out the result issue
This https://github.com/sayanarijit/expandvars-rs/blob/main/src/lib.rs#L97
fails with
thread 'tests::test_expandvars_get_default' panicked at 'assertion failed: `(left == right)`
left: `"${FOO-default}"`,
right: `"default"`', src/lib.rs:97:9parser impl: https://github.com/sayanarijit/expandvars-rs/blob/main/src/parser.rs#L30
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I feel like I'm missing something very simple and basic... But can't put a finger on it.
pares_fragemnt's call to parse_constant feels greedy, that it may consume more input than intended... Shouldn't it end on a `, unless under"`?
sayanarijit: You should start using permalinks, that contain the commit ID. There is an option for that in github.
Now
parse_closing_brace is explicitly gobbling your brace. The is nothing that matches a zero-width string, try using take_while in parse_constant.
This makes me thing of: https://play.rust-lang.org/?version=stable&mode=debug&edition=2021&gist=ffe576bfff1c92f727c671cf1fa595f5
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Other than where you'd use them?
that depends on the encoding that's being used, it sounds kind of like LEB128 to me
designed for compact storage. so some fields are a single byte whenever possible or 2 bytes when it cant be avoided
I havent heard of LEB128 before haha
Is there a way to group lines with a common prefix, think the output of find? I feel like I'm looking for hashmap recursion.
Should I parse to a collection of char slices and then copy those into a hashmap tree?
hi people, I'm trying to do something like:
let build_string = take_while1(is_alphanumeric);
delimited(char('"'), build_string, char('"'))(input)but I get this error:
type mismatch resolving
<&str as InputTakeAtPosition>::Item == u8expectedchar, foundu8
any idea how can I fix it?
it worked, thanks!