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package do

type Void struct{}

type Result[T any] interface {
	Unwrap() (T, error)
}

type defaultResult[T any] struct {
	val T

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Goal

The goal of this experiment is to try and implement the minimum requirements for the existence of a generic-style Option type in Go, similar to what we know from other languages, such as Java or Rust.

Motivation

Provide a fluent approach to error handling in Go which focuses on highlighting the "happy path", while being 100% idiomatic with Go's error handling convention.

NOTE: The core type is an interface called Option, having a single requirement:

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def time_until_reset() do
  today = :erlang.date()
  now = :erlang.time()
  now_in_sec = :calendar.datetime_to_gregorian_seconds({today, now})
  days_until_next_monday = 8 - :calendar.day_of_the_week(today)

  midnight = {0, 0, 0}

  next_monday_in_sec =
    :calendar.datetime_to_gregorian_seconds(

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This is a simple grayscale filter implementening image.Image. It can be used in place where an image.Image is expected.

img, err := loadImage("input.jpg")
// check error

err := saveImage(&GrayscaleFilter{img})
//check error

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Daily Idea: Use CNNs to Categorize Apps, Based on Their App Store Screenshots

The idea is rather simple and feasible, but as of this moment, not really useful. It just popped up in my mind, and I decided to write it down in case someone is looking for a ML challenge to work on. The idea is very simple:

1. Use the iTunes Search API to download app screenshots and categorize them by folders, corresponding to the names of categories that those apps have been featured in.
2. Teach a simple convolutional neural network (CNN) to categorize apps based on screenshots provided
3. Try and evaluate the NNs capabilities using screenshots that are not present in the model.

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// src/index.ts

import React, { Component } from 'react';
import {
    StyleSheet,
    Text,
    View,
    ViewStyle,
    TextStyle
} from 'react-native';

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Kotlin Basics: Create Executable Kotlin JARs, using Gradle

Kotlin is great for creating small command-line utilities, which can be packaged and distributed as normal JAR files. This short tutorial will show you how to:

• Set up a Gradle project that supports Kotlin
• Add a starting function
• Configure your build to call this function when you execute your JAR.

Setting up Kotlin dependencies

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public class DateUtil {

  public static Date asDate(LocalDate localDate) {
    return Date.from(localDate.atStartOfDay().atZone(ZoneId.systemDefault()).toInstant());
  }

  public static Date asDate(LocalDateTime localDateTime) {
    return Date.from(localDateTime.atZone(ZoneId.systemDefault()).toInstant());
  }

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Hamcrest Cheatsheet

Collection Matchers

Check if a collection contains a single item

assertThat(collection, hasItem("item1"));
assertThat(collection, not(hasItem("item2")));

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Setting Up a New Mac for Development

Command-Line Utilities

Homebrew

An absolute must. If you have ever worked with apt-get on Ubuntu, you know that it's the absolute developer bliss. Homebrew (or brew for short) is the missing package manager for OSX. Not only does it allow you to install/unisnstall/manage software with a few simple commands, the same way that apt-get does. It allows you to access and install ports of most of the cross-platform utilities that you might be familiar with from Linux, over to OSX.

Installing Brew

Simply open a new terminal and execute the following command:

ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)"