beautifhy 1.1.3

A Hy pretty-printer / code formatter / beautifier.

🦑 Beautifhy

A Hy beautifier / code formatter / pretty-printer / enhanced REPL.

Probably compatible with Hy 1.0.0 and later.

Install

$ pip install -U beautifhy

REPL

Beautifhy comes with a REPL that implements multi-line editing, completion, live input validation and live syntax highlighting.

$ hy-repl

The behaviour of the repl may be modified with the following environment variables.

• HY_HISTORY: Path to a file for storing command history. Defaults to ~/.hy-history.
• HY_PYGMENTS_STYLE: The name of a pygments style to use for highlighting. Defaults to lightbulb.
• HY_LIVE_COMPLETION: If set, enables live/interactive autocompletion in a dropdown menu as you type. Defaults to off.

Usage: pretty-printer and syntax highlighter

From the command line, to pretty-print the file core.hy:

$ beautifhy core.hy

gives the output

(import toolz [first second last])

 ;; * Utility things
 ;; -----------------------------------------

(defmacro defmethod [#* args]
  "Define a multimethod (using multimethod.multimethod).
  For example, the Hy code

  `(defmethod f [#^ int x #^ float y]
    (// x (int y)))`

  is equivalent to the following Python code:

  `@multimethod
  def f(x: int, y: float):
      return await x // int(y)`

  You can also define an asynchronous multimethod:

  `(defmethod :async f [#* args #** kwargs]
    (await some-async-function #* args #** kwargs))`
  "
  (if (= :async (first args))
    (let [f (second args) body (cut args 2 None)]
      `(defn :async [hy.I.multimethod.multimethod] ~f ~@body))
    (let [f (first args) body (cut args 1 None)]
      `(defn [hy.I.multimethod.multimethod] ~f ~@body))))


(defn slurp [fname #** kwargs]
  "Read a file and return as a string.
  kwargs can include mode, encoding and buffering, and will be passed
  to open()."
  (let [f (if (:encoding kwargs None) hy.I.codecs.open open)]
    (with [o (f fname #** kwargs)]
      (o.read))))


(defmacro rest [xs]
  "A slice of all but the first element of a sequence."
  `(cut ~xs 1 None))

To apply syntax highlighting (no pretty-printing), do

$ hylight core.hy

You can use stdin and pipe by replacing the filename with -:

$ beautifhy core.hy | hylight -

which will pretty-print core.hy and then syntax highlight the output.

To convert python code to Hy (using py2hy), autoformat, then apply syntax highlighting, do

$ pip3 install py2hy
$ python3 -m py2hy some_code.py | beautifhy - | hylight -

Acknowledgements

The whole library uses pygments. hy-repl also uses prompt-toolkit. Plus, of course, Hy, whose REPL hy-repl extends. The autoformatter relies on polymorphic dispatch provided by multimethod.

Docs

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