A major mode for editing Tengo script files in GNU Emacs.

Tengo is a small, dynamic, fast, secure scripting language for Go. This package provides syntax highlighting, indentation, and navigation support for Tengo source files (.tengo).

• Syntax Highlighting: Comprehensive highlighting for keywords, built-ins, constants, operators, strings, and comments.
• Context-Aware Indentation:
  • Smart indentation for braces {}, parentheses (), and brackets [].
  • Robust Logic: Correctly ignores braces found inside strings or comments (e.g., x := "{" will not trigger indentation).
• Navigation:
  • Support for beginning-of-defun (C-M-a) and end-of-defun (C-M-e).
  • Works with named functions (func foo()) and variable-assigned anonymous functions (foo := func()).
• Imenu Support: Indexing for top-level functions and variable declarations for quick navigation.
• Electric Support: Integration with electric-indent-mode.

1. Download tengo-mode.el to a directory in your load-path (e.g., ~/.emacs.d/lisp/).
2. Add the following to your Emacs configuration (.emacs or init.el):

(add-to-list 'load-path "~/.emacs.d/lisp/")
(require 'tengo-mode)

If you have the file saved locally:

(use-package tengo-mode
  :load-path "~/.emacs.d/lisp/"
  :mode "\\.tengo\\'")

(use-package tengo-mode
  :ensure t
  :mode "\\.tengo\\'")

The default indentation is 4 spaces. You can change this by setting tengo-indent-offset:

(setq tengo-indent-offset 2) ; Set indentation to 2 spaces

To automatically close brackets and braces, it is recommended to enable electric-pair-mode globally or specifically for Tengo:

(add-hook 'tengo-mode-hook 'electric-pair-mode)

tengo-mode inherits from prog-mode, so standard Emacs movement keys apply.

Based on the tengo-vim plugin and the official Tengo language documentation.