update readme

README.md

@@ -2,12 +2,36 @@
 
 Rust support library for Semaphore
 
-## Build static lib via ffi
+## Example
 
-Build e.g. for iOS simulator:
+```rust
+// generate identity
+let id = Identity::new(b"hello");
 
-`cargo build --release --target=aarch64-apple-ios-sim`
+// generate merkle tree
+const LEAF: Hash = Hash::from_bytes_be([0u8; 32]);
 
-Generate header file:
+let mut tree = PoseidonTree::new(21, LEAF);
+let (_, leaf) = id.commitment().to_bytes_be();
+tree.set(0, leaf.into());
 
-`cbindgen ./src/lib.rs -c cbindgen.toml | grep -v \#include | uniq > libsemaphore.h`
+let root: BigInt = tree.root().into();
+dbg!(root);
+
+let merkle_proof = tree.proof(0).expect("proof should exist");
+let root = tree.root().into();
+
+// change signal and external_nullifier here
+let signal = "hello".as_bytes();
+let external_nullifier = "123".as_bytes();
+
+let nullifier_hash = generate_nullifier_hash(&id, external_nullifier);
+
+let config = SnarkFileConfig {
+    zkey: "./snarkfiles/semaphore.zkey".to_string(),
+    wasm: "./snarkfiles/semaphore.wasm".to_string(),
+};
+
+let proof = generate_proof(&config, &id, &merkle_proof, external_nullifier, signal).unwrap();
+let success = verify_proof(&config, &root, &nullifier_hash, signal, external_nullifier, &proof).unwrap();
+```