Simply Language Support for VS Code

Editor support for the Simply programming language (.sim).

Features

• Simply appears as a language mode for .sim files and in Change Language Mode (Ctrl+K M).
• Syntax highlighting for types, control flow, logical operators, built-ins, strings, booleans, numbers, comments, and operators.
• Live lexer/parser/type diagnostics while you type.
• Red squiggles and entries in the VS Code Problems panel.
• Validation of unsaved files.
• Command: Simply: Validate Current File.

Runtime requirement

The extension uses the official Simply CLI for diagnostics. Install the runtime once:

python -m pip install simply-lang

Confirm it is available:

simply --help

Then install this extension from the VS Code Marketplace. After installation, .sim files are recognized anywhere on your computer; the Simpy source repository does not need to be cloned.

If simply is installed somewhere that is not on VS Code's PATH, configure Simply: Executable Path (simply.executablePath) with the executable's full path.

How live diagnostics work

For an open .sim document, the extension runs:

simply diagnostics

and sends the unsaved editor contents through standard input. The CLI returns machine-readable JSON generated by the same lexer, parser, and semantic analyzer used by the Simply interpreter.

Development

From this directory you can create a VSIX package with:

npm run package

or publish, after authenticating a Marketplace publisher, with:

npm run publish

See the repository's DISTRIBUTION.md for the complete release procedure.