krdln

#![crate_type="lib"]

pub enum Bool {
    True,
    Other(char), // try reordering variants
    False,
}

use Bool::*;

krdln

krdln's blog

Everything you need to know about constructors

^{2022-05-03, tags: C++, notes}

Default arguments are awesome!

Don't try to avoid them just because some other langs cough Rust cough don't have them!

krdln

#[allow(dead_code)]
// BASIC STRUCTURES
// ================
pub type Result<T> = ::std::result::Result<T,Error>;

#[derive(Debug,Copy,Clone,Eq,PartialEq)]
pub enum Reason {
    NegativeMapLength,
    OutOfRange,
    UnknownReason

krdln

#!/bin/bash

# rustdatehash: computes a git commit hash for a nightly from a given date.
# Works from about 2015-03-01
# usage: ./rustdatehash yyyy-mm-dd

set -e
set -u
set -o pipefail

krdln

...


macro_rules! nada {
    () => { unsafe { std::mem::uninitialized() } }
}

#[derive(Debug)]
struct Konnection {
    hp : String,

krdln

use std::num::Wrapping;

enum Instr {
    Inc(Wrapping<u8>),
    Move(isize),
    Loop(Box<[Instr]>),
    Print
}
use Instr::*;

krdln

use std::collections::BTreeMap;

extern crate typemap;
use typemap::{TypeMap, Key};

/// Keys for my ECS
trait MyKey: Key where <Self as Key>::Value: Clone {}

struct Ecs {
    // just an example layout. totally not cache-friendly

krdln

fn main() {
{
	let em = entity_manager;
	em.entities().filter_map(|entity|
		Some(entity)
			.and_then(|tuple|
				entity_manager
					.get_component::<X>(&tuple.0)
					.map(|obj|tuple.tup_append(obj))
			)

krdln

In fork-join concurrency scenario (here's an example of what the interface may look like) it may happen that we would want to pass Arc<Mutex<Vec<&mut int>>> to child threads (you can imagine that instead of int there's really big structure that parent thread could access only by reference, so I think it's a pretty reasonable scenario).

So we want to wrap Vec<&mut int> in a Mutex, but that requires Send and our vector doesn't fulfill Send. So to be able to do that, we may just remove Send bound from Mutex::new. We may think that it won't introduce any unsafety, because Send or 'static bound will be checked by spawn or similar methods anyway.

But unfortunately, now we are able to pass Arc<Mutex<Rc>> too, which for sure shouldn't be legal, because of internal, non-thread safe, mutability of Rc.

So my proposed solution is to keep Send bound for Mutex::new, but decouple Send from 'static. Send would only mean "has Sync env

krdln

#![feature(unboxed_closures, unboxed_closure_sugar)]

use std::rt::thread::Thread;
use std::kinds::marker::InvariantType;
use std::mem::transmute;

fn main() {
    let mut arr = [0, 1, 2, 3, 4];
    let _ = { // change _ to _bg and it fails to compile!
        let mut handle = arr.mut_iter(); // ref|:| ICEd rustc