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Clojure

Lem’s clojure-mode provides syntax highlighting, LSP support and nREPL integration, CIDER-compatible keybindings:

  • full-featured Clojure language mode with syntax highlighting, indentation, and LSP integration
  • nREPL client for interactive development with eval, macroexpand, and documentation commands
  • REPL mode with history, namespace tracking, and connection management
  • Clojure-specific tools: inspector, test runner, stacktrace navigation, and detective integration

With a comprehensive test suite covering the bencode protocol, indentation, and mode functionality.

Features

Core Mode (clojure-mode.lisp)

  • syntax highlighting for Clojure/ClojureScript/EDN files
  • Clojure-specific indentation with customizable rules
  • rainbow parentheses support
  • namespace detection and tracking, display namespace in modeline
  • file type support: .clj, .cljs, .cljc, .cljx, .edn

nREPL Integration (nrepl-client.lisp, repl.lisp)

  • full nREPL protocol implementation using bencode
  • interactive REPL with command history
  • connection management (nrepl-connect, nrepl-disconnect)
  • session handling (nrepl-clone-session, nrepl-close-session)
  • async/sync message sending
  • eval commands: clojure-eval-last-sexp, clojure-eval-defun, clojure-eval-region, clojure-eval-buffer
  • macroexpand support: clojure-macroexpand-1, clojure-macroexpand-all
  • documentation lookup: clojure-describe-symbol

Development Tools

  • Inspector (inspector.lisp): Browse Clojure data structures interactively
  • Test Runner (test-runner.lisp): Run tests with results display and navigation
  • Stacktrace (stacktrace.lisp): Navigate exceptions with source jumping
  • Detective (detective.lisp): Context menu integration for Clojure-specific actions
  • Tools (tools.lisp): Code actions, refactoring, and utilities

LSP Support (lsp-config.lisp)

  • integration with clojure-lsp for advanced IDE features
  • root patterns: deps.edn, project.clj, build.boot, shadow-cljs.edn

Commands

Evaluation Commands

  • clojure-eval-defun - Evaluate top-level form
  • clojure-eval-last-sexp - Evaluate expression before point
  • clojure-eval-region - Evaluate selected region
  • clojure-eval-buffer - Evaluate entire buffer
  • clojure-load-file - Load current file
  • clojure-switch-to-repl - Switch to REPL buffer
  • clojure-set-namespace - Change namespace
  • toggle-clojure-paren-coloring- Toggle rainbow parentheses

Keybindings (CIDER-compatible) 

C-c C-c    clojure-eval-defun
C-x C-e    clojure-eval-last-sexp
C-c C-e    clojure-eval-last-sexp
C-c C-r    clojure-eval-region
C-c C-k    clojure-load-file
C-c C-l    clojure-load-file
C-c C-z    clojure-switch-to-repl
C-c M-n    clojure-set-namespace-from-buffer

Macro Expansion

  • clojure-macroexpand-1 (C-c Return) - Single-step expansion
  • clojure-macroexpand-all (C-c M-m) - Full expansion
  • Popup buffer with syntax highlighting

Documentation

  • clojure-describe-symbol - Show docstring
  • clojure-describe-symbol-at-point (C-c C-d d) - Doc at point
  • Popup buffer for documentation display

Inspector

  • clojure-inspector-mode with navigation
  • clojure-inspect - Inspect arbitrary expression
  • clojure-inspect-last-sexp (C-c I) - Inspect sexp
  • History navigation (l/Backspace to go back)
  • Refresh capability (g)

Test Runner

  • clojure-run-test-at-point (C-c C-t t) - Run test under cursor
  • clojure-run-tests (C-c C-t n) - Run tests in namespace
  • clojure-run-all-tests (C-c C-t a) - Run all tests
  • clojure-rerun-last-test (C-c C-t l) - Rerun last test
  • Color-coded pass/fail/error display
  • Navigation between failures (n/p)

Stacktrace Navigation

  • clojure-stacktrace-mode with keybindings
  • clojure-show-last-exception (C-c C-x)
  • Clickable stack frames to jump to source
  • Toggle Java frames visibility (j)
  • Frame navigation (n/p/Tab)

Detective Integration (Lem’s interactive menu)

  • Regex patterns for all definition types:
    • Functions: defn, defn-, defmulti, defmethod
    • Macros: defmacro
    • Types: defprotocol, defrecord, deftype, definterface
    • Variables: def, defonce
    • Namespaces: ns
    • Tests: deftest, defspec
  • Auto-setup via mode hook

Context Menu

  • Context menu with evaluation actions
  • Items: Evaluate Expression, Evaluate Defun, Inspect Value, Run Test, Show Documentation
  • Auto-setup via mode hook

ClojureScript Support (Partial)

  • File type registration for .cljs, .cljc, .cljx, .edn
  • Shadow-cljs integration (future enhancement)
  • Figwheel support (future enhancement)

Refactoring Tools

  • clojure-align-let (C-c C-a l) - Align let bindings
  • clojure-align-map (C-c C-a m) - Align map literals
  • clojure-cycle-privacy (C-c C-p) - Toggle defn/defn-
  • clojure-add-require (C-c C-a r) - Add require clause
  • clojure-toggle-keyword-string (C-c C-’) - Toggle :keyword/“string”
  • clojure-thread-first - Convert to -> form

LSP Integration

  • clojure-lsp configuration
  • Project detection via deps.edn, project.clj, build.boot, shadow-cljs.edn
  • Installation instructions

Syntax Highlighting

  • TextMate-style language definition
  • Special forms (40+)
  • Built-in functions (100+)
  • Keywords, strings, regex literals
  • Numeric literals (decimal, hex, ratios)
  • Character literals
  • Metadata and deref
  • clojure-beginning-of-defun / clojure-end-of-defun
  • clojure-indent-sexp (C-M-q)

The original PR comes with a full test suite.

It was done with the help of Claude Code.