use std::evm::{Evm, RawMem, RawOps, RawStorage, StorPtr, mem}

struct Inner {

value: u256,

}

struct Outer {

inner: Inner,

}

struct MemOuter {

inner: Inner,

}

fn abi_encode(value: u256) -> ! uses (ops: mut RawOps) {

ops.mstore(addr: 0, value: value)

ops.return_data(offset: 0, len: 32)

}

fn read_inner() -> u256

uses (outer: Outer)

{

outer.inner.value

}

fn write_inner(value: u256)

uses (outer: mut Outer)

{

outer.inner.value = value

}

fn mem_read(value: u256) -> u256 {

let mut tmp = MemOuter { inner: Inner { value: 0 } }

tmp.inner.value = value

tmp.inner.value

}

#[contract_init(NestedStruct)]

fn init() uses (evm: mut Evm) {

let len = evm.code_region_len(runtime)

let offset = evm.code_region_offset(runtime)

let dest = mem::alloc(len)

evm.codecopy(dest: dest, offset: offset, len: len)

evm.return_data(offset: dest, len: len)

}

#[contract_runtime(NestedStruct)]

fn runtime() uses (evm: mut Evm) {

let mut outer: StorPtr<Outer> = evm.stor_ptr(0)

with (outer, RawOps = evm) {

let selector = evm.calldataload(0) >> 224

match selector {

0xb849fac8 => { // write_inner(uint256)

let value = evm.calldataload(4)

write_inner(value)

abi_encode(value: value)

}

0xd164e48d => { // read_inner()

abi_encode(value: read_inner())

}

0x806f30cd => { // mem_read(uint256)

let value = evm.calldataload(4)

abi_encode(value: mem_read(value))

}

_ => evm.return_data(offset: 0, len: 0)

}

}

}