Racket fixw

A Racket formatter that add/remove some whitespaces but respects newline.

🔋 Status

It should work as expected, except some rules for macros and special forms are missing.

🖨️ Example

before

#lang racket

(define(fib n )
(if (<= n 1)
1
(+ (fib  (- n 1))
(fib (- n 2)) )))

after

#lang racket

(define (fib n)
  (if (<= n 1)
      1
      (+ (fib (- n 1))
         (fib (- n 2)))))

✈️ Performance

• format a 5k lines file in 100ms on a 6 years old laptop

The biggest Racket file class-internal.rkt in racket/racket repo has almost 5k lines, so I think it's fast enough.

✨ Features

• fix indent
• respect newline
• works for unbalanced code
• remove trailing spaces
• force only one space between two tokens with several exceptions
• force only one empty line at the end of the file
  • make it configurable
• raco integration
• read scmindent compatible configuration file
• skip code that surrounded by special comments
• support range formatting
• a configurable system looks like macro but allows user customize the formatting
  • support sort require
  • support keyword arguments and default arguments

📑 todo

• refactor
  • isolate the lexer workarounds and special escape comments processing
  • simplify the core logic

🚀 Run

# install
raco pkg install fixw
# show help
raco fixw -h
# read from stdin and output formatted text to stdout
raco fixw
# format current directory recursively
raco fixw .

🤔 docs

See online docs.

🖇️ See also

• fmt - a Racket formatter that calculate optimal layout
• scmindent - a general lisp indenter