chore: add more examples, refactoring

Signed-off-by: Henry Gressmann <mail@henrygressmann.de>

4 files changed, 108 insertions, 0 deletions

diff --git a/examples/archive.rs b/examples/archive.rs
new file mode 100644
index 0000000..7c93205
--- /dev/null
+++ b/examples/archive.rs
@@ -0,0 +1,29 @@
+use color_eyre::eyre::Result;
+use tinywasm::{parser::Parser, types::TinyWasmModule, Module, Store};
+
+const WASM: &str = r#"
+(module
+  (func $add (param $lhs i32) (param $rhs i32) (result i32)
+    local.get $lhs
+    local.get $rhs
+    i32.add)
+  (export "add" (func $add)))
+"#;
+
+fn main() -> Result<()> {
+    let wasm = wat::parse_str(WASM).expect("failed to parse wat");
+    let module = Parser::default().parse_module_bytes(&wasm)?;
+    let twasm = module.serialize_twasm();
+
+    // now, you could e.g. write twasm to a file called `add.twasm`
+    // and load it later in a different program
+
+    let module: Module = TinyWasmModule::from_twasm(&twasm)?.into();
+    let mut store = Store::default();
+    let instance = module.instantiate(&mut store, None)?;
+    let add = instance.exported_func::<(i32, i32), i32>(&store, "add")?;
+
+    assert_eq!(add.call(&mut store, (1, 2))?, 3);
+
+    Ok(())
+}
diff --git a/examples/linking.rs b/examples/linking.rs
new file mode 100644
index 0000000..f278266
--- /dev/null
+++ b/examples/linking.rs
@@ -0,0 +1,41 @@
+use color_eyre::eyre::Result;
+use tinywasm::{Module, Store};
+
+const WASM_ADD: &str = r#"
+(module
+  (func $add (param $lhs i32) (param $rhs i32) (result i32)
+    local.get $lhs
+    local.get $rhs
+    i32.add)
+  (export "add" (func $add)))
+"#;
+
+const WASM_IMPORT: &str = r#"
+(module
+  (import "adder" "add" (func $add (param i32 i32) (result i32)))
+  (func $main (result i32)
+    i32.const 1
+    i32.const 2
+    call $add)
+  (export "main" (func $main))
+)
+"#;
+
+fn main() -> Result<()> {
+    let wasm_add = wat::parse_str(WASM_ADD).expect("failed to parse wat");
+    let wasm_import = wat::parse_str(WASM_IMPORT).expect("failed to parse wat");
+
+    let add_module = Module::parse_bytes(&wasm_add)?;
+    let import_module = Module::parse_bytes(&wasm_import)?;
+
+    let mut store = Store::default();
+    let add_instance = add_module.instantiate(&mut store, None)?;
+
+    let mut imports = tinywasm::Imports::new();
+    imports.link_module("adder", add_instance.id())?;
+    let import_instance = import_module.instantiate(&mut store, Some(imports))?;
+
+    let main = import_instance.exported_func::<(), i32>(&store, "main")?;
+    assert_eq!(main.call(&mut store, ())?, 3);
+    Ok(())
+}
diff --git a/examples/simple.rs b/examples/simple.rs
new file mode 100644
index 0000000..6f79c0f
--- /dev/null
+++ b/examples/simple.rs
@@ -0,0 +1,22 @@
+use color_eyre::eyre::Result;
+use tinywasm::{Module, Store};
+
+const WASM: &str = r#"
+(module
+  (func $add (param $lhs i32) (param $rhs i32) (result i32)
+    local.get $lhs
+    local.get $rhs
+    i32.add)
+  (export "add" (func $add)))
+"#;
+
+fn main() -> Result<()> {
+    let wasm = wat::parse_str(WASM).expect("failed to parse wat");
+    let module = Module::parse_bytes(&wasm)?;
+    let mut store = Store::default();
+    let instance = module.instantiate(&mut store, None)?;
+    let add = instance.exported_func::<(i32, i32), i32>(&store, "add")?;
+
+    assert_eq!(add.call(&mut store, (1, 2))?, 3);
+    Ok(())
+}
diff --git a/examples/wasm-rust.rs b/examples/wasm-rust.rs
index 112222c..b57a1da 100644
--- a/examples/wasm-rust.rs
+++ b/examples/wasm-rust.rs
@@ -1,6 +1,22 @@
 use color_eyre::eyre::Result;
 use tinywasm::{Extern, FuncContext, Imports, MemoryStringExt, Module, Store};
 
+/// Examples of using WebAssembly compiled from Rust with tinywasm.
+///
+/// These examples are meant to be run with `cargo run --example wasm-rust <example>`.
+/// For example, `cargo run --example wasm-rust hello`.
+///
+/// To run these, you first need to compile the Rust examples to WebAssembly:
+///
+/// ```sh
+/// ./examples/rust/build.sh
+/// ```
+///
+/// This requires the `wasm32-unknown-unknown` target, `binaryen` and `wabt` to be installed.
+/// `rustup target add wasm32-unknown-unknown`.
+/// https://github.com/WebAssembly/wabt
+/// https://github.com/WebAssembly/binaryen
+///
 fn main() -> Result<()> {
     let args = std::env::args().collect::<Vec<_>>();
     if args.len() < 2 {