eV+ in VS Code: Language Support for Omron Robot Programs

Simon Maddison / October 2026 (310 Words, 2 Minutes)

Overview
Why bother
What you get
Built from the manual
Trying it

Overview

Omron Adept robots are programmed in eV+ (and its older sibling V+), a language that dates back decades and shows it. The official editor does the job, but it’s a long way from a modern code editor. vscode-evplus brings eV+ / V+ programs (.pg, .v2) into VS Code: highlighting, hover help, completion, diagnostics and navigation. MIT-licensed.

Why bother

eV+ has a few traps that bite anyone coming from another language. The big one: everything after a ; is a comment. So this line

a = 1 ; b = 2

only assigns a. Nothing warns you, the robot just doesn’t do the second half. Add a large program split across many .PROGRAM blocks, GOTO labels, and a reference manual you have to keep open in another window, and small mistakes are easy to make and slow to find. An editor that knows the language catches most of them before the program ever reaches the controller.

What you get

Highlighting for control flow, instructions, functions, system switches and parameters, radix numbers (^HFF, ^B1010), precision points (#pick), string variables ($name), labels and .PROGRAM / .END blocks, with folding.
Hover shows the manual’s syntax line for the keyword under the cursor.
Completion for 260+ keywords with their type and syntax, and signature help that tracks which parameter you’re on.
Diagnostics for code hiding after a ;, GOTO targets that don’t exist, and unpaired .PROGRAM / .END.
Navigation: every program in the Outline panel, go-to-definition and find references across the workspace, and Ctrl+T to jump to any program by name.
Snippets and auto-indent for the usual blocks (IF, WHILE, DO/UNTIL, FOR, CASE).

Built from the manual

The keyword data isn’t typed in by hand. A script reads an extraction of the eV+ Language Reference Guide and generates both the keyword list (name, type and syntax for each entry) and the keyword patterns in the grammar. When the manual changes, the extension is regenerated rather than patched. Only the syntax lines are committed. If you own the manual you can regenerate locally with the fuller descriptions for richer hover text.

The grammar is covered by tokenisation snapshot tests, so a change that breaks highlighting on an existing construct fails the test run.

Trying it

It isn’t on the marketplace yet. Build it from source:

npm install
npm run package
./install.sh

install.sh installs the extension on both the WSL and Windows sides of VS Code. Reload, open a .pg file, and go.

Source is on GitHub.

-SM

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