comby

Simple replacement

$ comby 'console.log(:[arg])' 'logger.info(:[arg])' [.js]

$ comby 'foo(:[x])' 'bar(:[x])' [src/] -matcher [.py]

$ comby 'old' 'new' -match-only

$ comby 'pattern' 'replacement' -review

$ comby 'old' 'new' -in-place [file.go]

$ comby 'old' 'new' -diff [file.js]

comby matchtemplate rewritetemplate [path] [options]

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.

-matcher ext

File extension matcher (.py, .js, etc.)

Only show matches, don't rewrite

Modify files in place

Show unified diff output

Interactive review mode

Read from stdin

Write to stdout

Count matches only

Target directory

:[name]

Match any expression

Match balanced expression

Match across lines

Anonymous hole (discard)

Better than regex for nested structures. Does not support indentation-sensitive languages (Python, Haskell).

sed(1), ast-grep(1), semgrep(1)