Alexandre Marangoni Costa alexandremcosta

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Git Handbook

Reward system

A company is planning a way to reward customers for inviting their friends.
They're planning a reward system that will give a customer points for each confirmed invitation they played a part into.
The definition of a confirmed invitation is one where another invitation's invitee invited someone.

The inviter gets (1/2)^k points for each confirmed invitation, where k is the level of the invitation:

level 0 (people directly invited) yields 1 point
level 1 (people invited by someone invited by the original customer) gives 1/2 points
level 2 invitations (people invited by someone on level 1) awards 1/4 points and so on

Deadlock detected,
The system is infected.
Zombie processes
Haunt orphaned guests.

Abort transactions,
While we break the loop.
Don’t crash the node,
It’s a dependency soup.

What a trumpet taught me about code

My best friend is a musician, I’m a coder. Professionally and also as our favorite hobbies. He uses instruments to create songs, I use languages to create apps. We often fall into parallels between both worlds, but yesterday’s conversation went somewhere new.

He told me he bought a trumpet. No previous experience, never touched one before. I asked if he was going to take classes or figure it out himself. He laughed… already figuring it out himself, obviously. So he walked me through it.

First he figured out the mechanics. How much the sound changes when he presses the first valve, the second, the third. He knows a little trombone, so he could pick up the different mouth positions, each one produces a different note in a different range.

	class Weather::Interpolation
	def initialize(x, y, z, xi, yi)
	@x, @y, @z, @xi, @yi = x, y, z, xi, yi
	end

	def calc
	# if any location closer than 10km, return this location
	close_location = distances.index {\|d\| d < 10}
	close_location ? @z[close_location] : interpolation
	end

	defmodule MigrateRedis do
	require Logger

	@from [host: "127.0.0.1", port: 6379]
	@to [host: "127.0.0.1", port: 6379]

	def migrate(from \\ @from, to \\ @to) do
	{:ok, from} = Redix.start_link(from)
	{:ok, to} = Redix.start_link(to)

	defmodule Downloader do
	@moduledoc"""
	Download streams of bytes from URLs.
	Useful to transfer large files with low RAM usage.

	## Example with `ExAWS.S3.upload/3`

	```elixir
	url
	\|> Downloader.stream_body!()

	MIT License

	Permission is hereby granted, free of charge, to any person obtaining a copy
	of this software and associated documentation files (the "Software"), to deal
	in the Software without restriction, including without limitation the rights
	to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
	copies of the Software, and to permit persons to whom the Software is
	furnished to do so, subject to the following conditions:

	The above copyright notice and this permission notice shall be included in all

	# List Comprehensions
	squares = [x**2 for x in range(10)]
	even_squares = [x**2 for x in range(10) if x % 2 == 0]

	# Dictionary Comprehensions
	squared_dict = {x: x**2 for x in range(10)}

	# Lambda Functions
	add = lambda a, b: a + b

	-- =============================================================================
	-- A single-file Neovim configuration inspired by AstroNvim's UX conventions
	-- with a minimal, readable setup.
	-- =============================================================================
	--
	-- REQUIREMENTS:
	-- Neovim >= 0.11 (uses vim.lsp.config/enable API and LspProgress event)
	-- git (lazy.nvim bootstrap and gitsigns)
	-- make (telescope-fzf-native build step)
	-- A Nerd Font (icons in neo-tree, lualine, bufferline, dashboard)

Alexandre Marangoni Costa alexandremcosta

This is a Markdown page

Reward system

What a trumpet taught me about code

Then came the first AHA-moment.