simple.nvim

Neovim plugin for the Simple programming language.

Features

• Filetype detection for .spl files with proper indent and comment settings
• LSP integration with auto-detection of the Simple language server (src/app/lsp/)
• Tree-sitter support with registration and query path management (src/compiler/parser/treesitter/queries/)
• Math block rendering with conceal for m{ ... } syntax, inline Unicode preview, and LSP hover (LaTeX + Unicode)
• Brief view for code overview (fold to signatures only)
• User commands for testing, building, linting, and formatting
• Health checks via :checkhealth simple

Requirements

• Neovim >= 0.9 (0.11+ recommended for native LSP config)
• Simple language compiler (bin/simple) for LSP and test/build commands
• Optional: nvim-treesitter for tree-sitter parser management

Installation

lazy.nvim

{
  "ormastes/simple.nvim",
  ft = "simple",
  opts = {},
}

packer.nvim

use {
  "ormastes/simple.nvim",
  config = function()
    require("simple").setup()
  end,
}

Manual (from project)

Add the plugin directory to your runtime path in init.lua:

vim.opt.rtp:prepend("/path/to/simple/src/app/nvim_plugin")
require("simple").setup()

Configuration

require("simple").setup({
  lsp = {
    enabled = true,
    cmd = { "simple", "lsp" },        -- or { "bin/simple", "lsp" }
    root_markers = { "simple.sdn", ".git" },
    settings = {},
    on_attach = nil,                    -- custom on_attach callback
  },
  math = {
    enabled = true,
    conceal = true,                     -- conceal m{ } delimiters
    float_on_hover = true,              -- show float on CursorHold
    update_delay = 100,                 -- ms debounce for re-rendering
    highlight_group = "SimpleMathBlock",
  },
  treesitter = {
    ensure_installed = true,
    query_path = nil,                   -- auto-detects from project
  },
  commands = {
    enabled = true,
    test_cmd = { "bin/simple", "test" },
  },
  keymaps = {
    enabled = true,
    prefix = "<localleader>s",
  },
})

Commands

Command	Description
:SimpleTest [file]	Run tests on current file or specified path
:SimpleBrief	Collapse all folds to show only signatures
:SimpleBriefExpand	Expand all folds
:SimpleLspRestart	Restart the Simple LSP server
:SimpleLspLog	Open the LSP log file
:SimpleMathToggle	Toggle math block rendering
:SimpleBuild [args]	Run build command with optional arguments
:SimpleLint	Run the Simple linter
:SimpleFormat	Run the Simple formatter
:SimpleInfo	Show plugin information

Default Keymaps

When keymaps.enabled = true, the following keymaps are set for Simple files (prefix defaults to <localleader>s):

Keymap	Action
<localleader>st	Run test
<localleader>sb	Brief view
<localleader>se	Expand all
<localleader>sm	Toggle math
<localleader>sr	Restart LSP
<localleader>si	Plugin info
<localleader>sl	Lint
<localleader>sf	Format

Math Block Rendering

Simple supports math blocks with the m{ ... } syntax:

val result = m{ x^2 + y^2 }
val gradient = m{ d/dx (x^2) }

Math rendering works at two levels:

1. LSP hover (primary): The LSP server at src/app/lsp/handlers/hover.spl detects m{ } blocks and renders them using src/lib/math_repr.spl:

   • render_latex_raw() -- raw LaTeX output ($$x^{2} + y^{2}$$)
   • to_pretty() -- Unicode pretty text (x² + y²)
   • to_md() -- LaTeX markdown ($x^{2} + y^{2}$)
   • MathJax SVG rendering via src/lib/mathjax.spl (requires Node.js)

2. Inline conceal (supplementary): With math.conceal = true, the m{ and } delimiters are concealed, the interior is highlighted with SimpleMathBlock, and a Unicode preview is shown as virtual text at end-of-line (e.g., x² + y²). Hovering over a math block shows the original source in a floating window.

Tree-sitter Queries

The plugin automatically locates tree-sitter queries from the Simple project at src/compiler/parser/treesitter/queries/. These include:

• highlights.scm (538 lines) - Syntax highlighting (100+ keywords, 50+ scope types, operators, literals)
• locals.scm (411 lines) - Scope tracking and variable resolution
• folds.scm (404 lines) - Code folding regions
• textobjects.scm (587 lines) - Semantic text objects for selection/navigation
• injections.scm (373 lines) - Embedded language support (15+ injected languages including SQL, HTML, regex)
• indents.scm (454 lines) - Auto-indentation rules

Health Check

Run :checkhealth simple to verify:

• Neovim version compatibility
• LSP server binary availability
• Tree-sitter parser installation
• Math rendering status
• Project structure detection

License

Same license as the Simple language project.