Cannot parse nested tagged elements

[bhavyakukkar]

As far as I understand, EDNs can be nested tags i.e.

#pow2 #pow3 2

which is expected to be parsed as:

Tagged("pow2", Tagged("pow3", Int(2)))

From the spec:

Upon encountering a tag, the reader will first read the next element (which may itself be or comprise other tagged elements)

I also verified this with the python implementation where the following assertion succeeds:

expand python code

import edn_format
edn_format.add_tag("pow2", lambda x: x*x)
edn_format.add_tag("pow3", lambda x: x*x*x)
assert(edn_format.loads("#pow2 #pow3 2") == 64)

---

However, at present this library fails to parse the same example with code UnexpectedEOF:

expand rust code

use clojure_reader::edn::{self, Edn};

fn main() {
  assert_eq!(
    edn::read_string("#pow2 #pow3 2").unwrap(),
    Edn::Tagged("pow2", Box::new(Edn::Tagged("pow3", Box::new(Edn::Int(2)))))
  );
}

thread 'main' panicked at examples/foo.rs:5:39:
called `Result::unwrap()` on an `Err` value: EdnError { code: UnexpectedEOF, line: Some(1), column: Some(14), ptr: Some(13) }
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace

[Grinkers]

Thanks, this is an issue. If possible, I would not like to use the python implementation as a reference. However it does seem correct.

Here's a clojure repro

(edn/read-string {:readers {'pow2 #(* % %) 'pow3 #(* % % %)}} "#pow2 #pow3 2")
64

[Grinkers]

Sorry for the big edit. I've moved my notes to #10

The potential fix for this issue, a regression in 0.5.0 is #9

[bhavyakukkar]

thanks for the super quick fix!