Monogate Forge — VS Code extension

EML-lang language support for VS Code. Writing EML needs nothing else; install the Forge CLI (pip install "monogate-forge[lsp]") to add compile, analysis and verification. No license or account.

What you get for free (no CLI required)

Syntax highlighting for .eml files (TextMate grammar)
- Keywords: module use as const type unit fn extern let mut where requires ensures assume while if else …
- Builtins: exp ln log sin cos tan sqrt pow eml abs clamp asin acos atan sinh cosh tanh floor pi dot sum and the builtin calls min max atan2 log10 exp10 step arcsin arccos arctan log2 cbrt expm1 log1p hypot fmod ceil trunc round
Snippets for the common patterns: fn, fnverify, module, usestdlib, requires, ensures, targetfpga, verify, plus the @verify Hoare-contract template with requires/ensures pre-filled
Bracket auto-close, comment toggle, indent rules
Static completion: keyword + builtin suggestions
Outline view: regex-driven document symbols (fn, const, type)

What unlocks with the Forge CLI

The Forge CLI (pip install "monogate-forge[lsp]"; see monogateforge.com/get-started) ships an LSP server and the compiler. Once installed, the extension auto-detects both binaries on PATH and lights up:

Real-time diagnostics — lex, parse, and chain-order errors as you type
Hover — chain order, cost class, FPGA cycles for fns; structural class + chain delta for builtin transcendentals
Rich completion — local decls + 87 stdlib symbols (math, ml, signal, linalg, control, constants)
Cross-file goto-definition — into bundled stdlib + sibling user .eml files
Find all references + workspace-wide rename (rename blocks builtins; validates new names)
Document symbols + outline — typed via the real parser, not regex
Document links — ctrl-click use stdlib::* clauses to jump to source
Format-on-save — re-emit canonical EML in-process via the LSP
Workspace symbol search (Ctrl+T) — fuzzy match across every indexed file
FPGA status bar — LUT / DSP / cycle estimates per file
Inline profile lenses — chain order + cost class above each fn header
Compile commands for all 36 targets (palette + right-click)

Every target compiles locally, with no license or account. Some need something in the source to emit: Verilog, SystemVerilog, VHDL and Chisel a @target(fpga) function; SPICE, KiCad and JLCPCB @spice_* components; Lean, Coq and Isabelle a @verify block. JLCPCB writes its three-file bundle to <name>_jlcpcb/ beside the source.

Without eml-lsp, the extension still runs eml-compile --profile-only on save and puts each parse, import, unit, refinement and chain-order error on its line.

Install

Install this extension from the VS Code marketplace.
Open any .eml file — syntax + snippets + outline work immediately.
To enable real-time diagnostics, hover, completion, format, and compile-to-anything: visit https://monogateforge.com/get-started for the CLI.

Architecture

File	Role
`src/extension.ts`	Entry point — registers providers + commands
`src/forgeCli.ts`	Resolves `eml-compile` and `eml-lsp` on PATH
`src/lspClient.ts`	Spawns `eml-lsp` and connects vscode-languageclient
`src/editorOnly.ts`	Static completion + regex outline (no CLI needed)
`src/profileProvider.ts`	CodeLens provider — runs `--profile-only`, parses dashboard
`src/diagnostics.ts`	Save-triggered diagnostics fallback when LSP unavailable
`src/cliDiagnostics.ts`	Reads each error's location from `eml-compile` output (no `vscode` import)
`language-configuration.json`	Bracket auto-close, comment toggle
`syntaxes/eml.tmLanguage.json`	TextMate grammar
`snippets/eml.json`	Snippet library

The LSP discovery happens once per session (cached). When the LSP isn't available, the extension falls back to: static completion provider, regex outliner, save-time diagnostics from eml-compile when it is installed, and a one-shot install hint (no nag — appears once per session).