fix: follow-up pyo3 API changes in module/function registration

Author: martonilles

src/lib.rs

@@ -1,11 +1,25 @@
-use pyo3::prelude::*;
 use pyo3::exceptions;
-
-
+use pyo3::prelude::*;
 
 // This defines a python module. pyo3 will copy the rust doc comment
 // below into a python docstring
 
+/// Demangles a mangled c++ linker symbol name and returns it as a string
+#[pyfunction]
+fn demangle(mangled: String) -> PyResult<String> {
+    let symbol = ::cpp_demangle::Symbol::new(&mangled[..]).map_err(|error| {
+        exceptions::PyValueError::new_err(("Could not demangle symbol", error.to_string()))
+    })?;
+    let demangled = symbol.demangle(&Default::default()).map_err(|error| {
+        exceptions::PyValueError::new_err((
+            "Could not format demangled name as string",
+            error.to_string(),
+        ))
+    })?;
+
+    Ok(demangled)
+}
+
 /// A package for demangling C++ linker symbols
 ///
 /// This package provides python bindings for the rust crate
@@ -24,23 +38,7 @@ use pyo3::exceptions;
 /// ...
 /// ValueError: ('Could not demangle symbol', 'mangled symbol is not well-formed')
 #[pymodule]
-fn cpp_demangle(_py: Python, m: &PyModule) -> PyResult<()> {
-    // This adds a function to the python module:
-    /// Demangles a mangled c++ linker symbol name and returns it as a string
-    #[pyfn(m)]
-    fn demangle(mangled: String) -> PyResult<String> {
-        let symbol = ::cpp_demangle::Symbol::new(&mangled[..]).map_err(|error| {
-            exceptions::PyValueError::new_err(("Could not demangle symbol", error.to_string()))
-        })?;
-        let demangled = symbol.demangle(&Default::default()).map_err(|error| {
-            exceptions::PyValueError::new_err((
-                "Could not format demangled name as string",
-                error.to_string(),
-            ))
-        })?;
-
-        Ok(demangled)
-    }
-
-    Ok(())
+mod cpp_demangle {
+    #[pymodule_export]
+    use super::demangle;
 }