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Dependency Injection in Functional Programming

There exist several DI frameworks / libraries in the Scala ecosystem. But the more functional code you write the more you'll realize there's no need to use any of them.

A few of the most claimed benefits are the following:

• Dependency Injection.
• Life cycle management.
• Dependency graph rewriting.

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Introduction to scalaz-stream

Every application ever written can be viewed as some sort of transformation on data. Data can come from different sources, such as a network or a file or user input or the Large Hadron Collider. It can come from many sources all at once to be merged and aggregated in interesting ways, and it can be produced into many different output sinks, such as a network or files or graphical user interfaces. You might produce your output all at once, as a big data dump at the end of the world (right before your program shuts down), or you might produce it more incrementally. Every application fits into this model.

The scalaz-stream project is an attempt to make it easy to construct, test and scale programs that fit within this model (which is to say, everything). It does this by providing an abstraction around a "stream" of data, which is really just this notion of some number of data being sequentially pulled out of some unspecified data source. On top of this abstraction, sca

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Branching

Quick Legend

Description, Instructions, Notes

Instance	Branch

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import javax.persistence.EntityManager;

import com.google.inject.AbstractModule;
import com.google.inject.Inject;
import com.google.inject.Singleton;
import com.google.inject.persist.PersistService;
import com.google.inject.persist.jpa.JpaPersistModule;

public class DatabaseModule extends AbstractModule {
	

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#include <string>
#include <functional>

using namespace std;

template <typename T>
struct Maybe{
  T just;
  bool isNothing;
};

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#!/bin/bash
# bash generate random alphanumeric string
#

# bash generate random 32 character alphanumeric string (upper and lowercase) and 
NEW_UUID=$(cat /dev/urandom | tr -dc 'a-zA-Z0-9' | fold -w 32 | head -n 1)

# bash generate random 32 character alphanumeric string (lowercase only)
cat /dev/urandom | tr -dc 'a-zA-Z0-9' | fold -w 32 | head -n 1

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package org.codefx.lab.stream;

import java.util.Collection;
import java.util.Objects;
import java.util.Optional;
import java.util.function.BinaryOperator;
import java.util.function.Supplier;

/**
 * Finds a certain customer in a collection of customers.

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-- show running queries (pre 9.2)
SELECT procpid, age(clock_timestamp(), query_start), usename, current_query 
FROM pg_stat_activity 
WHERE current_query != '<IDLE>' AND current_query NOT ILIKE '%pg_stat_activity%' 
ORDER BY query_start desc;

-- show running queries (9.2)
SELECT pid, age(clock_timestamp(), query_start), usename, query 
FROM pg_stat_activity 
WHERE query != '<IDLE>' AND query NOT ILIKE '%pg_stat_activity%' 

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Selections and Multiple Cursors in Sublime Text 3

A handy list of selection shortcuts.

Here are the official docs: Keyboard and Mouse

Mouse

Building blocks:

• Add to selection: Ctrl
• Subtract from selection: Alt

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// vim: syntax=shell

$JAR=/usr/lib/spark/lib/spark-examples.jar
$KEY=MoissinB

# Create cluster with 1st step
aws emr create-cluster  --profile $KEY \
                        --name "Moissinb Cluster" \
                        --release-label emr-5.10.0 \
                        --applications Name=Spark \