vindvaki / atom-autocomplete-julia

An autocomplete+ provider for the Julia language

autocomplete-julia: Auto-Completion for Julia in Atom

Uses the new built-in autocomplete+ API.

Features

• Fuzzy matching within the context of the current line
• Type icons and hints for suggestions
• Falls back to other available providers for awareness of buffer contents

TODO

Project aware suggestions

I.e. parse project (or at least the current buffer) and show suggestions. This includes things like knowing that completions in lib/completions.jl (of this package) comes from the module Base.REPL.REPLCompletions because of the line

using Base.REPL.REPLCompletions: completions, non_identifier_chars

This could be done by evaluating the using/import statements in the Julia child process, but we don't want to do that because that can lead to evaluating code with side effects.

Using the REPL completions is essentially a local maximum: It works well and can be very useful if refined, but to do project awareness well we need a more sophisticated infrastructure (e.g. use the official julia-parser.scm or JuliaParser.jl)

Known issues

Sometimes the Julia child process starts using up 100% CPU

Implementation details

You can ignore this section if you're not interested in improving this package.

The package is in its early stages. Just a few lines of code really, so it's the perfect time to jump in and improve it.

Atom (the client)

• Manages the Julia child process
• Communicates with the Julia child process through stdio
• Interprets the suggestion results from the Julia child process

Julia (the server)

See lib/completions.jl

Completions algorithm

The heavy lifting is done by

Base.REPL.REPLCompletions.completions(string, pos)

from Julia. The output of this function is a tuple of the form

(array_of_completions, subrange_being_completed, success?)

Interface

The input is a pair of lines:

line in the buffer               <-- first line
cursor position within the line  <-- second line

The output should be zero or more lines of the form

typeof(eval(parse(completion))) completion

if parse(eval(completion)) exists. If not, additional heuristics need to be applied to determine the type.