Niko for VS Code
Syntax highlighting, language-server features, and debugging for the
Niko programming language. Current through Niko 2.0 Alpha 25.
Features
- Syntax highlighting for
.niko files (TextMate grammar) —
includes match expressions with guards and list/record patterns,
import/use/pkg: statements, ask, and all builtins
- Language server (
niko2 lsp, stdio): squiggles for parse and type
errors as you type, completion for keywords/builtins/your names, hover
docs and inferred types, go-to-definition (follows imported modules
and pkg: packages, even cross-file), format-document, rename
refactoring (scope-aware, incl. cross-file export renames across
import/use graphs), and
module-aware diagnostics across import/use graphs
- Debugging (
niko2 debug, DAP): line breakpoints — including
conditional breakpoints — step over / in / out, call stack, locals
with list/record expansion, the program's say output in the Debug
Console, and expression evaluation in the Debug Console / watch
window. Works across files: imported modules and used modules both
load under the debugger, breakpoints can target any module, and every
stack frame opens its own file
Install
You need Python 3 with the niko2 package importable (e.g. the
Niko-v2.0 folder on PYTHONPATH).
From the packaged file (recommended): in VS Code, run
Extensions: Install from VSIX… and pick niko-0.25.0.vsix.
From source: copy this folder to a scratch dir, run npm install
inside client/, then npx vsce package, then install the produced
.vsix.
Settings: niko.pythonPath — the Python used to launch the language
server and debug adapter (default python3).
Debugging a file
Open a .niko file and press F5 (the "Debug current Niko file"
configuration), or create a launch config:
{
"type": "niko",
"request": "launch",
"name": "Debug Niko file",
"program": "${file}"
}
Optional launch attributes: stopOnEntry (pause on the first line) and
inputTimeout (seconds to wait for ask input, default 30).
Notes: breakpoints, stepping, and stack traces work across imported and
used modules (each stack frame opens its own file). ask for input is
answered through a Niko-specific DAP reverse input request — debug
clients that don't answer it (including stock VS Code) give the program
"" after the timeout.
Grammar tests
node test-grammar.js tokenizes sample lines with the real TextMate
engine and asserts the scopes; it also verifies the grammar's builtin
list against the checker's canonical BUILTIN_NAMES. The two test-only
packages should go in a scratch copy, not this folder:
cp -r . /tmp/niko-gram && cd /tmp/niko-gram
npm install --no-save vscode-textmate vscode-oniguruma
NIKO_REPO=/path/to/Niko-v2.0 node test-grammar.js
