REPL based workflow

Intro

This is a recommended workflow in order to boost productivity, when writing julia code using a conventional text editor (e.g., vim, emacs, gedit) and executing it via the Julia REPL (Read, Evaluate, and Print Loop).

The Golden rule

The golden rule of the workflow is very simple: DO NOT CLOSE THE JULIA REPL UNTIL IT IS STRICTLY NEEDED. Each time you close the REPL most of the just-in-time (JIT) compiled code will be deleted. The next time you open the REPL all your code will be JIT-compiled again, causing a significant overhead for large problems.

A simple scenario

Let us assume that we are coding in a file code.jl and we wand to execute it, see results, fix problems, execute it again, etc. The way you don't want to do this is as follows