More
author |
Steve Losh <steve@stevelosh.com> |
date |
Wed, 23 Dec 2020 09:31:29 -0500 |
parents |
1fa04416fcdb |
children |
(none) |
(eval-when (:compile-toplevel :load-toplevel :execute)
(ql:quickload '(:adopt :with-user-abort) :silent t))
(defpackage :pick
(:use :cl)
(:export :toplevel :*ui*))
(in-package :pick)
;;;; Configuration ------------------------------------------------------------
(defparameter *version* "0.0.1")
(defparameter *separator* (string #\Newline))
(defparameter *interactive-input* *query-io*)
(defparameter *interactive-output* *query-io*)
;;;; Functionality ------------------------------------------------------------
(defun read-lines (stream)
(loop :for line = (read-line stream nil)
:while line
:collect line))
(defun matchesp (string choices)
(member string choices :test #'string-equal))
(defun prompt (format-string &rest args)
(loop :for line = (progn
(apply #'format *interactive-output* format-string args)
(force-output *interactive-output*)
(read-line *interactive-input*))
:do (cond
((matchesp line '("y" "yes")) (return t))
((matchesp line '("n" "no" "")) (return nil)))))
(defun filter-many (choices)
(loop
:with width = (1+ (reduce #'max choices :key #'length :initial-value 0))
:for choice :in choices
:when (prompt "~A~vA[yN] " choice (- width (length choice)) #\space)
:collect choice))
(defun filter-one (choices)
(loop :for choice :in choices
:for i :from 0
:do (format *interactive-output* "~36R) ~A~%" i choice)
:collect choice)
(let ((i (parse-integer (read-line *interactive-input*) :radix 36)))
(if (or (minusp i) (>= i (length choices)))
(error "Bad choice ~d" i)
(list (elt choices i)))))
(defun output (results)
(loop :for (r . remaining) :on results
:do (write-string r)
:when remaining :do (write-string *separator*)))
(defun run-many (choices)
(output (filter-many choices)))
(defun run-one (choices)
(output (filter-one choices)))
;;;; User Interface -----------------------------------------------------------
(defparameter *examples*
'(("Pick some Python files and count their lines:"
. "wc -l `pick *.py`")
("Search for some processes and interactively pick some to kill:"
. "ps aww | awk 'NR > 1 { print $1, $5 }' | grep htop | pick | cut -d' ' -f1 | xargs kill")))
(defparameter *option-help*
(adopt:make-option 'help
:help "Display help and exit."
:long "help"
:short #\h
:reduce (constantly t)))
(defparameter *option-version*
(adopt:make-option 'version
:help "Display version information and exit."
:long "version"
:reduce (constantly t)))
(defparameter *option-separator*
(adopt:make-option 'separator
:help "Print SEP between records when outputting (default: newline)."
:long "separator"
:short #\s
:initial-value *separator*
:parameter "SEP"
:reduce #'adopt:last))
(defparameter *option-null*
(adopt:make-option 'null
:result-key 'separator
:help "Use null bytes as separators for output."
:long "null"
:short #\0
:reduce (constantly (string #\nul))))
(defparameter *option-one*
(adopt:make-option 'one
:help "Pick a single line instead of picking one-by-one."
:long "one"
:short #\o
:reduce (constantly t)
:initial-value nil))
(defparameter *option-many*
(adopt:make-option 'many
:result-key 'one
:help "Pick multiple lines, asking one-by-one (the default)."
:long "many"
:short #\O
:reduce (constantly nil)))
(adopt:define-string *help-text*
"pick displays its arguments one-by-one on standard error and prompts you ~
interactively to choose some of them. The chosen items will be printed to ~
standard output.~@
~@
An argument of - will cause pick to read lines from standard input as ~
choices. Using an explicit - instead of reading from standard input when no ~
arguments are present prevents something like 'pick `ls -1 | grep foo`' from ~
silently hanging forever if no files match.~@
~@
Using the --one argument changes the behaviour of pick. Instead of ~
picking several lines from the input by asking one-by-one, all of the lines ~
are presented at once and the user is prompted to pick one of them with ~
a prefix.
~@
This version was inspired by the pick program described in 'The UNIX ~
Programming Environment'.")
(defparameter *ui*
(adopt:make-interface
:name "pick"
:usage "[OPTIONS]"
:summary "interactively pick some things"
:help *help-text*
:examples *examples*
:contents (list *option-help*
*option-version*
*option-separator*
*option-null*
*option-one*
*option-many*)))
(defmacro exit-on-ctrl-c (&body body)
`(handler-case
(with-user-abort:with-user-abort (progn ,@body))
(with-user-abort:user-abort () (adopt:exit 130))))
(defun toplevel ()
(exit-on-ctrl-c
(handler-case
(multiple-value-bind (arguments options) (adopt:parse-options *ui*)
(cond ((gethash 'help options) (adopt:print-help-and-exit *ui* :option-width 24))
((gethash 'version options) (write-line *version*) (adopt:exit)))
(with-open-file (*interactive-input* "/dev/tty" :direction :input)
(let ((*separator* (gethash 'separator options))
(*interactive-output* *error-output*)
(arguments (mapcan (lambda (arg)
(if (string= "-" arg)
(read-lines *standard-input*)
(list arg)))
arguments)))
(funcall (if (gethash 'one options)
#'run-one
#'run-many)
arguments))))
(error (c) (adopt:print-error-and-exit c)))))