README.md

axil

axil is a terminal user interface for tree-sitter, the parser generator tool and incremental parsing library.

axil lets you explore and query syntax trees interactively, including:

• Browse the full syntax tree in an interactive TUI with vim-style navigation (h/j/k/l), collapsible nodes, and half-page scrolling.

• Search for node types with /, jumping between matches with n/N.

• Run tree-sitter queries live with ?, seeing matched nodes highlighted in real time.

• Yank the source text of any node to the clipboard with y.

• Mouse support for click-to-navigate and scroll wheel.

• Print the syntax tree to stdout for non-interactive use, with optional --query highlighting.

• Supports 15+ languages out of the box: Bash, C, C++, CSS, Go, HTML, and more.

If you need help with axil please feel free to open an issue. Feature requests and bug reports are always welcome!

Installation

axil should run on any system, including Linux, MacOS, and the BSDs.

The easiest way to install it is by using cargo, the Rust package manager:

cargo install axil

Otherwise, see below for the complete package list:

Cross-platform

Package Manager	Package	Command
Cargo	axil	cargo install axil
Homebrew	terror/tap/axil	brew install terror/tap/axil

Pre-built binaries

Pre-built binaries for Linux, MacOS, and Windows can be found on the releases page.

Usage

Running axil with a file path prints the syntax tree to stdout:

$ axil example.json
document [0:0..3:0]
  object [0:0..2:1]
    { [0:0..0:1] "{"
    pair [1:2..1:16]
      string [1:2..1:7]
        " [1:2..1:3] "\""
        string_content [1:3..1:6] "foo"
        " [1:6..1:7] "\""
      : [1:7..1:8] ":"
      string [1:9..1:16]
        " [1:9..1:10] "\""
        string_content [1:10..1:15] "hello"
        " [1:15..1:16] "\""
    } [2:0..2:1] "}"

The language is automatically detected from the file extension. When reading from stdin, pass --language explicitly:

$ echo '{"foo": "hello"}' | axil --language json

Interactive Mode

The --interactive flag opens the syntax tree in a full-screen TUI where you can browse and explore the tree. Navigation is vim-style: h/j/k/l to move around, Enter to collapse and expand nodes, and Space to select a node and view its details in an info panel.

$ axil main.rs --interactive

You can search for node types by pressing / and typing a pattern. Jump between matches with n and N. Press y on any node to yank its source text to the clipboard.

Tree-sitter Queries

The --query flag runs a tree-sitter query against the syntax tree and highlights matching nodes. In print mode, only nodes matching the query are shown:

$ axil main.rs --query '(function_item name: (identifier) @name)'

In interactive mode, press : to enter a query live. Matched nodes are highlighted in real time as you type, and you can jump between them with n and N.

Watch Mode

The --watch flag automatically reloads the syntax tree when the source file changes on disk. This is useful when editing a file in another window and watching the tree update in real time:

$ axil main.rs --interactive --watch

Keybindings

Key	Action
j / k	Move down / up
h / l	Move to parent / first child
g / G	Jump to top / bottom
Ctrl-u	Scroll up half page
Ctrl-d	Scroll down half page
Enter	Toggle collapse
Space	Toggle select
/	Search node types
n / N	Next / previous search match
:	Enter tree-sitter query
y	Yank node text to clipboard
Esc	Clear search
?	Toggle help
q	Quit

Prior Art

Check out tree-sitter, the parser generator tool and incremental parsing library.