rewrite of the book

Author: arihant2math

Diff for: src/SUMMARY.md

@@ -1,4 +1,9 @@
 # Summary
 
-- [Introduction](./intro.md)
-- [Writing Functions](./writing_functions.md)
+- [Introduction](introduction/index.md)
+- [Getting Started](getting_started/index.md)
+  - [Installation](getting_started/installation.md)
+  - [Initial Setup](getting_started/initial_setup.md)
+- [Interop](interop/index.md)
+  - [Calling Rust from Python](interop/rust_from_python.md)
+  - [Calling Python from Rust](interop/python_from_rust.md)

Diff for: src/getting_started/index.md

@@ -0,0 +1,4 @@
+# Getting Started
+
+- [Installation](./installation.md)
+- [Initial Setup](./initial_setup.md)

Diff for: src/getting_started/initial_setup.md

@@ -0,0 +1,73 @@
+# Initial Setup
+
+First `rustpython_vm` needs to be imported.
+If `rustpython` is installed, it can be imported as a re-export:
+```rust
+use rustpython::vm;
+```
+
+if `rustpython_vm` is installed, it can be imported just like any other module.
+
+```rust
+use rustpython::vm;
+
+fn main() -> vm::PyResult<()> {
+    vm::Interpreter::without_stdlib(Default::default()).enter(|vm| {
+        let scope = vm.new_scope_with_builtins();
+        let source = r#"print("Hello World!")"#;
+        let code_obj = vm
+            .compile(source, vm::compiler::Mode::Exec, "<embedded>".to_owned())
+            .map_err(|err| vm.new_syntax_error(&err, Some(source)))?;
+
+        vm.run_code_obj(code_obj, scope)?;
+
+        Ok(())
+    })
+}
+```
+
+This will print `Hello World!` to the console.
+
+## Adding the standard library
+If the `stdlib` feature is enabled,
+the standard library can be added to the interpreter by calling `add_native_modules`
+with the result of `rustpython_stdlib::get_module_inits()`.
+```rust
+use rustpython::vm as vm;
+use std::process::ExitCode;
+use vm::{Interpreter, builtins::PyStrRef};
+
+fn py_main(interp: &Interpreter) -> vm::PyResult<PyStrRef> {
+    interp.enter(|vm| {
+        let scope = vm.new_scope_with_builtins();
+        let source = r#"print("Hello World!")"#;
+        let code_obj = vm
+            .compile(source, vm::compiler::Mode::Exec, "<embedded>".to_owned())
+            .map_err(|err| vm.new_syntax_error(&err, Some(source)))?;
+
+        vm.run_code_obj(code_obj, scope)?;
+    })
+}
+
+fn main() -> ExitCode {
+    // Add standard library path
+    let mut settings = vm::Settings::default();
+    settings.path_list.push("Lib".to_owned());
+    let interp = vm::Interpreter::with_init(settings, |vm| {
+        vm.add_native_modules(rustpython_stdlib::get_module_inits());
+    });
+    let result = py_main(&interp);
+    let result = result.map(|result| {
+        println!("name: {result}");
+    });
+    ExitCode::from(interp.run(|_vm| result))
+}
+```
+
+to import a module, the following code can be used:
+```rust, no_run
+// Add local library path
+vm.insert_sys_path(vm.new_pyobj("<module_path>"))
+    .expect("add examples to sys.path failed");
+let module = vm.import("<module_name>", 0)?;
+```

Diff for: src/getting_started/installation.md

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+# Installation
+## Requirements
+RustPython requires Rust latest stable version to be installed
+
+## Stable
+The latest stable version of the library can be installed using the following command:
+```bash
+cargo add rustpython
+```
+
+or by adding the following to your `Cargo.toml`:
+```toml
+[dependencies]
+rustpython = "0.4"
+```
+
+## Nightly
+Nightly releases are built weekly and are released on git.
+```toml
+[dependencies]
+rustpython = { git = "https://github.com/RustPython/RustPython", tag = "2025-02-24-main-13" }
+```
+
+The tag should be pointed to the latest tag found at https://github.com/RustPython/RustPython/tags.
+
+## Features
+By default `threading`, `stdlib`, and `importlib` are enabled.
+### `bz2`
+If you'd like to use the `bz2` module, you can enable the `bz2` feature.
+### `stdlib`
+`stdlib` is the default feature that enables the standard library.
+### `sqlite`
+If you'd like to use the `sqlite3` module, you can enable the `sqlite` feature.
+### `ssl`
+If you'd like to make https requests, you can enable the ssl feature,
+which also lets you install the pip package manager.
+Note that on Windows, you may need to install OpenSSL, or you can enable the ssl-vendor feature instead,
+which compiles OpenSSL for you but requires a C compiler, perl, and make.
+OpenSSL version 3 is expected and tested in CI. Older versions may not work.
+

Diff for: src/interop/index.md

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+# Interpretation between Rust and Python
+- [Calling Rust from Python](./rust_from_python.md)
+- [Calling Python from Rust](./python_from_rust.md)

Diff for: src/interop/python_from_rust.md

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+# Calling Python from Rust
+TODO.

Diff for: src/interop/rust_from_python.md

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+# Calling Rust from Python
+## Structure
+```rust, ignore
+use rustpython::vm::pymodule;
+#[pymodule]
+mod test_module {
+    #[pyattr]
+    pub const THE_ANSWER: i32 = 42;
+
+    #[pyfunction]
+    pub fn add(a: i32, b: i32) -> i32 {
+        a + b
+    }
+
+    #[pyattr]
+    #[pyclass]
+    pub struct TestClass {
+        pub value: i32,
+    }
+
+    #[pyclass]
+    impl TestClass {
+        #[pygetset]
+        pub fn value(&self) -> i32 {
+            self.value
+        }
+
+        #[pymethod]
+        pub fn get_info(&self) -> i32 {
+            self.value * 2
+        }
+    }
+}
+```
+This code defines a Python module named `test_module` with two items:
+a constant named `THE_ANSWER` and a function named `add`.
+The `#[pymodule]` attribute is used to mark the module,
+and the `#[pyattr]` and `#[pyfunction]` attributes are used to mark the constant and function, respectively.
+
+RustPython allows for 3 types of items in a module:
+- Variables: Defined using the `#[pyattr]` attribute.
+- Functions: Defined using the `#[pyfunction]` attribute.
+- Classes: Defined using the `#[pyclass]` attribute.
+
+## General Configuration
+Most attributes have a `name` parameter that can be used to specify the name of the item in Python.
+If the `name` parameter is not provided, the Rust identifier is used as the name in Python.
+
+## Variables
+Variables are defined using the `#[pyattr]` attribute.
+A variable can either be a constant or a function.
+Note that classes are treated as attributes in RustPython
+and are annotated with `#[pyattr]` as well, but that can be done away with if needed.
+```rust, no_run
+#[pyattr]
+const THE_ANSWER: i32 = 42;
+// ... or
+#[pyattr]
+fn the_answer() -> i32 {
+    42
+}
+// ... or
+// this will cache the result of the function
+// and return the same value every time it is called
+#[pyattr(once)]
+fn cached_answer() -> i32 {
+    42
+}
+```
+
+## Valid Arguments
+
+Every return value must be convertible to PyResult. This is defined as IntoPyResult trait. So any return value of them must implement IntoPyResult. It will be PyResult<PyObjectRef>, PyObjectRef and any PyResult<T> when T implements IntoPyObject. Practically we can list them like:
+
+
+The `vm` paramter is just suffix. We add it as the last parameter unless we don't use `vm` at all - very rare case. It takes an object `obj` as `PyObjectRef`, which is a general python object. It returns `PyResult<String>`, which will turn into `PyResult<PyObjectRef>` the same representation of `PyResult`.
+
+Every return value must be convertible to `PyResult`. This is defined as `IntoPyResult` trait. So any return value of them must implement `IntoPyResult`. It will be `PyResult<PyObjectRef>`, `PyObjectRef` and any `PyResult<T>` when T implements `IntoPyObject`. Practically we can list them like:
+- Any `T` when `PyResult<T>` is possible
+- `PyObjectRef`
+- `PyResult<()>` and `()` as `None`
+- `PyRef<T: PyValue>` like `PyIntRef`, `PyStrRef`
+- `T: PyValue` like `PyInt`, `PyStr`
+- Numbers like `usize` or `f64` for `PyInt` and `PyFloat`
+- `String` for `PyStr`
+- And more types implementing `IntoPyObject`.
+
+The same could mostly be said about input arguments.
+
+## Functions
+Functions are defined using the `#[pyfunction]` attribute.
+```rust, no_run
+#[pyfunction]
+fn add(a: i32, b: i32) -> i32 {
+    a + b
+}
+```
+
+## Classes
+Classes are defined using the `#[pyclass]` attribute.
+```rust, no_run
+#[pyclass]
+pub struct TestClass {
+    pub value: i32,
+}
+#[pyclass]
+impl TestClass {
+}
+```
+### Associated Data
+TODO.
+### Methods
+TODO.
+### Getters and Setters
+TODO.
+### Class Methods
+TODO.
+### Static Methods
+TODO.
+### Inheritance
+TODO.

Diff for: src/introduction/index.md

@@ -0,0 +1,3 @@
+# Introduction
+
+RustPython is a Python interpreter written in Rust.