comby
structural code search and replace tool
TLDR
Simple replacement
$ comby 'console.log(:[arg])' 'logger.info(:[arg])' [.js]
Replace in directory$ comby 'foo(:[x])' 'bar(:[x])' [src/] -matcher [.py]
Preview changes$ comby 'old' 'new' -match-only
Interactive review$ comby 'pattern' 'replacement' -review
In-place modification$ comby 'old' 'new' -in-place [file.go]
Diff output$ comby 'old' 'new' -diff [file.js]
SYNOPSIS
comby matchtemplate rewritetemplate [path] [options]
DESCRIPTION
comby is a structural code search and replace tool for any language. Uses lightweight templates with holes (:[name]) to match code structures. Understands syntax of code blocks, strings, and comments.
PARAMETERS
-matcher ext
File extension matcher (.py, .js, etc.)-match-only
Only show matches, don't rewrite-in-place
Modify files in place-diff
Show unified diff output-review
Interactive review mode-stdin
Read from stdin-stdout
Write to stdout-count
Count matches only-d dir
Target directory
HOLE SYNTAX
:[name]
Match any expression:[name:e]
Match balanced expression:[[name]]
Match across lines:[_]
Anonymous hole (discard)
INSTALL
brew install comby
nix profile install nixpkgs#comby
CAVEATS
Better than regex for nested structures. Does not support indentation-sensitive languages (Python, Haskell).
