jpastuszek

use core::pin::Pin;
use core::marker::PhantomPinned;

#[derive(Debug)]
struct Unm(i32, PhantomPinned); // !Unpin
//struct Unm(i32); // Unpin

fn foo() -> Pin<Box<Unm>> {
    // PhantomPinned is !Unpin so Pin does not implement get_mut (disallowing mem::swap/replece and then move) nor into_inner (move out Unm of Box)
    Box::pin(Unm(1, PhantomPinned))

jpastuszek

#![feature(type_alias_impl_trait)]

use std::io::Read;
use std::io::Cursor;
    
struct B(String);
struct RefPairA<'b>(&'b B, String);

trait GetPair {
    fn pair(&self) -> (&str, &str);

jpastuszek

use std::any::{Any, TypeId};
use std::fmt::Debug;

pub trait Resource: Any + Debug {
    // this returns correct function for the Self to work on Box so that it can be casted and unboxed
    fn combine_fn(&self) -> fn(left: Box<dyn Resource>, right: Box<dyn Resource>) -> Box<dyn Resource>;
}

#[derive(Debug)]
struct File(u32);

jpastuszek

use std::sync::Mutex;
use std::sync::RwLock;
use std::sync::Arc;
use std::collections::HashMap;
use lazy_static::lazy_static;

lazy_static! {
    static ref CACHE: Mutex<HashMap<&'static str, Arc<RwLock<Option<u32>>>>> = Mutex::new(HashMap::new());
}

jpastuszek

use std::marker::PhantomData;

struct Connection(u32);

impl Connection {
    fn statement(&self) -> Statement {
        Statement(Raii(self.0), PhantomData)
    }
}

jpastuszek

#![feature(const_generics)]
#![feature(const_generic_impls_guard)]

trait CsvRecord<const COLS: usize> {
    fn columns() -> [&'static str; COLS];
    fn values(&self) -> [String; COLS];
}

struct Foo {
    id: u32,

jpastuszek

// https://stackoverflow.com/questions/50519147/double-mutable-borrow-error-in-a-loop-happens-even-with-nll-on
// https://github.com/rust-lang/rust/issues/54663
// This will complie with polonius: rustc +nightly -Zpolonius --edition=2018 /tmp/p.rs
struct Foo(u8);

impl Foo {
    fn even<'i>(&'i mut self) -> &'i u8 {
        loop {
            match self.next() {
                Some(even) => return even,

jpastuszek

use std::marker::PhantomData;
use std::convert::TryFrom;
use std::convert::TryInto;

#[derive(Debug)]
struct ConversionError;

struct ResultSet<T> {
    column_names: Vec<String>,
    rows: Vec<Vec<i32>>,

jpastuszek

use std::rc::Rc;

struct ResultSet {
    column_names: Rc<Vec<String>>,
    rows: Vec<Vec<i32>>,
}

impl ResultSet {
    fn pop(&mut self) -> Option<Row> {
        self.rows.pop().map(|columns| Row {

jpastuszek

struct ResultSet {
    column_names: Vec<String>,
    rows: Vec<Vec<i32>>,
}

impl ResultSet {
    fn get<'rs>(&'rs self, row_no: usize) -> Option<Row<'rs>> {
        self.rows.get(row_no).map(|columns| Row {
            column_names: self.column_names.as_slice(),
            columns: columns.as_slice(),