joom

let val plus = \(n:nat) \(m:nat) rec m {
      z           => n
    | s(x) with y => s(y)
    }
in let val pred = \(n : nat) rec n {
      z           => z
    | s(x) with y => x
    }
in let val minus = \(n:nat) \(m:nat) rec m {
      z           => n

macintux

%% Date formats in Erlang are a bit tricky to keep straight,
%% especially since the `calendar' library leverages Gregorian seconds
%% (seconds since year 0) rather than the more traditional UNIX epoch
%% seconds.
%%
%% This module illustrates the structures and conversions.

-module(erlang_dates).

-compile(export_all).

cmeiklejohn

Papers on Chain Replication

• Chain Replication for Supporting High Throughput and Availability; Robbert van Renesse, Fred B. Schneider; 2004
• Object Storage on CRAQ: High-Throughput Chain Replication for Read-Mostly Workloads; Jeff Terrace and Michael J. Freedman; 2009
• FAWN: A Fast Array of Wimpy Nodes; David G. Andersen, Jason Franklin, Michael Kaminsky, Amar Phanishayee, Lawrence Tan, Vijay Vasudevan; 2009
• Chain Replication in Theory and in Practice; Scott Lystig Fritchie; 2010
• HyperDex: A Distributed, Searchable Key-Value Store; Robert Escriva, Bernard Wong, Emin Gün Sirer; 2012
• [ChainReaction: a Causal+ Consistent Datastore based on Chain Replication](http://others.keleher

sdebnath

This gist captures what needs to be done to add a new field to Riak's Yokozuna
search index.

Sources:
- https://github.com/basho/yokozuna/issues/130
- http://riak-users.197444.n3.nabble.com/How-to-update-existed-schema-td4032143.html

The code below is for illustration purposes only. Use at your own risk.

1. Create/Update new schema file

frenchy64

Schema

I think of Schema as a runtime contracts library (I believe it does coercion and validation, but they seem related to me).

Pros

• small barrier to entry, thus immediately useful
  • just add a contract/coercion to a function and you're off
• can manipulate contracts as regular clojure data
• documentation

richhickey

(require '[clojure.core.async :as a])

(def xform (comp (map inc)
              (filter even?)
              (dedupe)
              (flatmap range)
              (partition-all 3)
              (partition-by #(< (apply + %) 7))
              (flatmap flatten)
              (random-sample 1.0)

seancribbs

%% @doc Reports on percentage of modules, functions and types that are
%% documented.
-module(edoc_stats).
-export([file/1, file/2, files/1, files/2, aggregate/1, report/1, report_files/1, report_files/2]).
-include_lib("xmerl/include/xmerl.hrl").
-import(xmerl_xpath, [string/2]).

-define(QUERY_FUNS, [ fun module_has_description/2
                    , fun functions_have_descriptions/2
                    , fun types_have_descriptions/2

john2x

Clojure Destructuring Tutorial and Cheat Sheet

(Related blog post)

Simply put, destructuring in Clojure is a way extract values from a datastructure and bind them to symbols, without having to explicitly traverse the datstructure. It allows for elegant and concise Clojure code.

Vectors and Sequences

david-christiansen

module FizzBuzzC

%default total

-- Dependently typed FizzBuzz, constructively

-- A number is fizzy if it is evenly divisible by 3
data Fizzy : Nat -> Type where
  ZeroFizzy : Fizzy 0
  Fizz : Fizzy n -> Fizzy (3 + n)

jeremyheiler

public class Main {

    public static final Object LOCK = new Object();

    public static void main(String[] args) throws InterruptedException {
        new Thread(new A()).start();
        new Thread(new B()).start();
    }

}