Python - Better error conversions

bindings/python/src/error.rs

@@ -0,0 +1,28 @@
+use pyo3::exceptions;
+use pyo3::prelude::*;
+use std::fmt::{Display, Formatter, Result as FmtResult};
+use tokenizers::tokenizer::Result;
+
+#[derive(Debug)]
+pub struct PyError(pub String);
+impl PyError {
+    pub fn from(s: &str) -> Self {
+        PyError(String::from(s))
+    }
+}
+impl Display for PyError {
+    fn fmt(&self, fmt: &mut Formatter) -> FmtResult {
+        write!(fmt, "{}", self.0)
+    }
+}
+impl std::error::Error for PyError {}
+
+pub struct ToPyResult<T>(pub Result<T>);
+impl<T> std::convert::Into<PyResult<T>> for ToPyResult<T> {
+    fn into(self) -> PyResult<T> {
+        match self.0 {
+            Ok(o) => Ok(o),
+            Err(e) => Err(exceptions::Exception::py_err(format!("{}", e))),
+        }
+    }
+}

bindings/python/src/lib.rs

@@ -1,5 +1,6 @@
 mod decoders;
 mod encoding;
+mod error;
 mod models;
 mod pre_tokenizers;
 mod token;