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@douglashill
douglashill / KeyboardTableView.swift
Last active Sep 8, 2021
A UITableView that allows navigation and selection using a hardware keyboard.
View KeyboardTableView.swift
// Douglas Hill, December 2018
// Made for https://douglashill.co/reading-app/
// Find the latest version of this file at https://github.com/douglashill/KeyboardKit
import UIKit
/// A table view that allows navigation and selection using a hardware keyboard.
/// Only supports a single section.
class KeyboardTableView: UITableView {
// These properties may be set or overridden to provide discoverability titles for key commands.
@dsemenovsky
dsemenovsky / confirmEtherTransaction.js
Created Jun 1, 2018
Confirm Ethereum transaction
View confirmEtherTransaction.js
function confirmEtherTransaction(txHash, confirmations = 10) {
setTimeout(async () => {
// Get current number of confirmations and compare it with sought-for value
const trxConfirmations = await getConfirmations(txHash)
console.log('Transaction with hash ' + txHash + ' has ' + trxConfirmations + ' confirmation(s)')
if (trxConfirmations >= confirmations) {
// Handle confirmation event according to your business logic
@dsemenovsky
dsemenovsky / getConfirmations.js
Created Jun 1, 2018
Get Ethereum transaction confirmations count
View getConfirmations.js
async function getConfirmations(txHash) {
try {
// Instantiate web3 with HttpProvider
const web3 = new Web3('https://rinkeby.infura.io/')
// Get transaction details
const trx = await web3.eth.getTransaction(txHash)
// Get current block number
const currentBlock = await web3.eth.getBlockNumber()
View watchTokenTransfers.js
function watchTokenTransfers() {
// Instantiate web3 with WebSocketProvider
const web3 = new Web3(new Web3.providers.WebsocketProvider('wss://rinkeby.infura.io/ws'))
// Instantiate token contract object with JSON ABI and address
const tokenContract = new web3.eth.Contract(
TOKEN_ABI, process.env.TOKEN_CONTRACT_ADDRESS,
(error, result) => { if (error) console.log(error) }
)
View watchEtherTransfers.js
function watchEtherTransfers() {
// Instantiate web3 with WebSocket provider
const web3 = new Web3(new Web3.providers.WebsocketProvider('wss://rinkeby.infura.io/ws'))
// Instantiate subscription object
const subscription = web3.eth.subscribe('pendingTransactions')
// Subscribe to pending transactions
subscription.subscribe((error, result) => {
if (error) console.log(error)
@yossorion
yossorion / what-i-wish-id-known-about-equity-before-joining-a-unicorn.md
Last active Nov 21, 2021
What I Wish I'd Known About Equity Before Joining A Unicorn
View what-i-wish-id-known-about-equity-before-joining-a-unicorn.md

What I Wish I'd Known About Equity Before Joining A Unicorn

Disclaimer: This piece is written anonymously. The names of a few particular companies are mentioned, but as common examples only.

This is a short write-up on things that I wish I'd known and considered before joining a private company (aka startup, aka unicorn in some cases). I'm not trying to make the case that you should never join a private company, but the power imbalance between founder and employee is extreme, and that potential candidates would

@simme
simme / debounce-throttle.swift
Created Dec 20, 2016
Swift 3 debounce & throttle
View debounce-throttle.swift
//
// debounce-throttle.swift
//
// Created by Simon Ljungberg on 19/12/16.
// License: MIT
//
import Foundation
extension TimeInterval {
@chriseth
chriseth / 0 README.md
Last active Jul 24, 2020
Formal verification for re-entrant Solidity contracts
View 0 README.md

This gist shows how formal conditions of Solidity smart contracts can be automatically verified even in the presence of potential re-entrant calls from other contracts.

Solidity already supports formal verification of some contracts that do not make calls to other contracts. This of course excludes any contract that transfers Ether or tokens.

The Solidity contract below models a crude crowdfunding contract that can hold Ether and some person can withdraw Ether according to their shares. It is missing the actual access control, but the point that wants to be made

View upgradeable.sol
/**
* Base contract that all upgradeable contracts should use.
*
* Contracts implementing this interface are all called using delegatecall from
* a dispatcher. As a result, the _sizes and _dest variables are shared with the
* dispatcher contract, which allows the called contract to update these at will.
*
* _sizes is a map of function signatures to return value sizes. Due to EVM
* limitations, these need to be populated by the target contract, so the
* dispatcher knows how many bytes of data to return from called functions.
@Koze
Koze / PhotosCameraRoll.m
Last active Feb 3, 2018
Getting Camera Roll with Photos.framework
View PhotosCameraRoll.m
PHFetchResult *result = [PHAssetCollection fetchAssetCollectionsWithType:PHAssetCollectionTypeSmartAlbum
subtype:PHAssetCollectionSubtypeSmartAlbumUserLibrary
options:nil];
PHAssetCollection *assetCollection = result.firstObject;
NSLog(@"%@", assetCollection.localizedTitle);
// Camera Roll