generator sample

Author: youknowone

examples/generator.rs

@@ -0,0 +1,51 @@
+use rustpython_vm as vm;
+use vm::{
+    builtins::PyIntRef,
+    protocol::{PyIter, PyIterReturn},
+    Interpreter, PyResult,
+};
+
+fn py_main(interp: &Interpreter) -> vm::PyResult<()> {
+    let generator = interp.enter(|vm| {
+        let scope = vm.new_scope_with_builtins();
+        let _ = vm.run_code_string(
+            scope.clone(),
+            r#"
+def gen():
+    for i in range(10):
+        yield i
+
+generator = gen()
+"#,
+            "".to_owned(),
+        )?;
+        let generator = scope.globals.get_item("generator", vm)?;
+        Ok(generator)
+    })?;
+
+    loop {
+        let r = interp.enter(|vm| {
+            let v = match PyIter::new(generator.clone()).next(vm)? {
+                PyIterReturn::Return(obj) => {
+                    PyIterReturn::Return(obj.try_into_value::<PyIntRef>(vm)?)
+                }
+                PyIterReturn::StopIteration(x) => PyIterReturn::StopIteration(x),
+            };
+            PyResult::Ok(v)
+        })?;
+        match r {
+            PyIterReturn::Return(value) => println!("{}", value),
+            PyIterReturn::StopIteration(_) => break,
+        }
+    }
+
+    Ok(())
+}
+
+fn main() {
+    let interp = vm::Interpreter::with_init(Default::default(), |vm| {
+        vm.add_native_modules(rustpython_stdlib::get_module_inits());
+    });
+    let result = py_main(&interp);
+    std::process::exit(interp.run(|_vm| result));
+}