However I am in fact scanning for all such structures in the input, so even if the attacker can insert bad cases, I think I should be able to still find the good ones, which is what matters in my case.
Returning to the original question, I'd take the specification, the expected data structure and find some sequence of 4+ bytes that's known ahead of time so that I could seek to it with
take_until
is there any way to have alt((a, b)) not return (&str, &str)
this is what i have
45 | pub fn alt<I: Clone, O, E: ParseError<I>, List: Alt<I, O, E>>(l: List) -> impl Fn(I) -> IResult<I, O, E> {
| ------------ required by this bound in `nom::branch::alt`
|
= note: expected enum `std::result::Result<(&str, &str), nom::internal::Err<(&str, nom::error::ErrorKind)>>`
found enum `std::result::Result<(&str, screen::settings::administration::parse_search::Criteria<'_>), nom::internal::Err<(&str, nom::error::ErrorKind)>>`
i think the issue is the two combinators return diff types, do they each need to return Either or something
Hello, I'm trying to write a parser that needs to parse Python-style variable names ([A-Za-z0-9_] characters, except the first character cannot be a number). I thought I would start by writing a custom version of nom::character::complete::alphanumeric1 that also accepts underscores, but when I tried copying it to my code and modifying it, I found that nom::traits is private. Any suggestions on the idiomatic way to do this with Nom?
/
tuple that returns a single slice
oo,
recognize looks like it'll help
I want to simplify this
fn ident(s: &[u8]) -> IResult<&[u8], &[u8]> {
recognize(preceded(
|i| if let Some(&l) = s.get(0) {
if letter(l) {
Ok((&s[1..], ()))
} else {
Err(Err::Error(ParseError::from_error_kind(s, ErrorKind::OneOf)))
}
} else {
Err(Err::Incomplete(Needed::Size(1)))
},
take_while(|b| matches!(b, b'A'..=b'Z' | b'a'..=b'z' | b'_' | b'0'..=b'9'))
))(s)
}
Hello! I'm having a problem with creating a custom errorkind and parser completness, in the docs for
alt it says "with a custom error type, it is possible to have alt return the error of the parser that went the farthest in the input data" but there seems to not be any documentation on how to do this
When all of my alt cases fail, then I'm getting an
Incomplete, not an error. How would I get my desired behaivior?
Here is the exact code I care about:
let (input, defs) = complete(many1(annotated_terminal(alt((
p_fn_named,
p_prim,
p_struct,
p_enum,
)))))(input)?;
I'm trying to parse many top-level definitions, and if the whole file is not parsed, then I want the error from why it wasn't able to parse
Thank you for any help!
and btw! I've been using nom to make a mixfix parser library, is there any interest in building tokenstream functionality into nom?
my idea is that we'd have nom::tokens just like nom::bytes with some combinators to do with taking tokens from a tokenstream
I also could just build it out into its own library which might be a better idea
Hi, I need to parse an expression which can be either an int literal or a float literal
So far I've been using
alt((float_literal, int_literal)).So far I've been using
number::complete::double to parse the float literal, but this caused trouble because double also accepts integers double("1") == 1.0. Is there an easy way to fix this?
does that make a diff
fn parse_date(input: &str) -> IResult<&str, DateTime<Utc>> {
DateTime::parse_from_str(input, "%F")
.map_err(|_| nom::Err::Error((input, /* here */)))
}
I have some problems and I do not really understand what is wrong with my code:
use nom::IResult;
use crate::types::JavaVersion;
use nom::bits::complete::take;
use crate::constants::MAGIC_NUMBER;
use nom::error::context;
use crate::constants::sizes::{MINOR_SIZE, MAJOR_SIZE}; // both are assigned a value of 2 respectively
use nom::sequence::tuple;
use nom::combinator::map;
pub fn parse_version_info(i: &[u8]) -> IResult<&[u8], JavaVersion> {
map(
tuple((
take(MINOR_SIZE),
take(MAJOR_SIZE)
)),
|(minor, major)| {
JavaVersion {
major,
minor,
}
}
)(i)
}
#[cfg(test)]
mod tests {
use crate::parser::{parse_class_file, parse_version_info};
use byteorder::{WriteBytesExt, BigEndian};
fn int2bytes(i: i32) -> Vec<u8> {
let mut bs = [0u8; std::mem::size_of::<i32>()];
bs.as_mut()
.write_i32::<BigEndian>(i)
.expect("Failed to convert to byte array");
bs.into_vec()
}
#[test]
fn test_version_info() {
let i = 0x3200;
let i = int2bytes(i).as_slice();
let version = parse_version_info(i);
}
}
|I get the following error:
error[E0308]: mismatched types
--> java-class-file\src\parser.rs:22:7
|
22 | )(i)
| ^ expected tuple, found `&[u8]`
|
= note: expected tuple `(_, usize)`
found reference `&[u8]`
error[E0308]: mismatched types
--> java-class-file\src\parser.rs:11:5
|
11 | / map(
12 | | tuple((
13 | | take(MINOR_SIZE),
14 | | take(MAJOR_SIZE)
... |
21 | | }
22 | | )(i)
| |________^ expected `&[u8]`, found tuple
|
= note: expected enum `std::result::Result<(&[u8], types::JavaVersion), nom::internal::Err<(&[u8], nom::error::ErrorKind)>>`
found enum `std::result::Result<((_, usize), types::JavaVersion), nom::internal::Err<_>>`
error: aborting due to 2 previous errors
I have no clue what I am doing wrong. Why exactly is it expected that the return type is a tuple here?
I want to return a IResult holding the rest of the u8 slice plus a JavaVersion that I parsed earlier
Hi there! A newbie from Uruguay here.
I've been working on a modsecurity parser for some weeks and I'm really glad I chose nom for this project. But I'm quite stucked right now.
I want this parser to be able to parse comments. This should be a very simple task, just reading from '#' until EOL.
What is the recommended way to achieve this?
Hey! I have a custom binary file that has tag bytes that denote the type of the next value. In total there are 13 different tag bytes and depending on the tag byte, I need to read in a different number of bytes afterwards. How would I do this in nom with just combining parsers? My current approach is to read in the byte (call take), and match over that one single byte, returning different parsers depending on the value it has.
The goal is to ditch that first byte read and somehow combine it with the match statement to create one single parser only.
The goal is to ditch that first byte read and somehow combine it with the match statement to create one single parser only.
@tanriol I kind of did that actually. Is there a tag specific to bytes? Or do I have to use
On a side note, is there a way to tell nom to only match the next N bytes on a parser? The binary file contains some kind of variable table that has its size declared using two bytes at the beginning. So I only want to apply my tag byte logic until those N bytes are passed. Afterwards other sub-parsers should take over.
tag("\x01") or tag([0x01]) for the time being?On a side note, is there a way to tell nom to only match the next N bytes on a parser? The binary file contains some kind of variable table that has its size declared using two bytes at the beginning. So I only want to apply my tag byte logic until those N bytes are passed. Afterwards other sub-parsers should take over.
hey folks, I'm trying to write an s-expression parser and I have a function that looks like this:
delimited(
char('('),
list_content,
preceded(multispace0, char(')')),
)(input)I want it to ignore whitespace and apparently that's causing issues. this function fails when called with the input ( 123 456 ) but doesn't when the input is ( 123 456 ) (note the extra space at the end!). any obvious reason why this might be? the error I get is: Err(Error(("", Char)))