eeef65b505
(for) is restored to clojure-like flatness.
(with) can be used without the nested list if you don't care about the
name.
Tests and examples updated.
109 lines
3.4 KiB
Hy
109 lines
3.4 KiB
Hy
;;; Hy anaphoric macros
|
|
;;
|
|
;; Copyright (c) 2013 James King <james@agentultra.com>
|
|
;; 2013 Paul R. Tagliamonte <tag@pault.ag>
|
|
;; 2013 Abhishek L <abhishek.lekshmanan@gmail.com>
|
|
;;
|
|
;; Permission is hereby granted, free of charge, to any person obtaining a
|
|
;; copy of this software and associated documentation files (the "Software"),
|
|
;; to deal in the Software without restriction, including without limitation
|
|
;; the rights to use, copy, modify, merge, publish, distribute, sublicense,
|
|
;; and/or sell copies of the Software, and to permit persons to whom the
|
|
;; Software is furnished to do so, subject to the following conditions:
|
|
;;
|
|
;; The above copyright notice and this permission notice shall be included in
|
|
;; all copies or substantial portions of the Software.
|
|
;;
|
|
;; THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
|
|
;; IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
|
;; FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
|
|
;; THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
|
|
;; LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
|
|
;; FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
|
|
;; DEALINGS IN THE SOFTWARE.
|
|
;;
|
|
;;; These macros make writing functional programs more concise
|
|
|
|
|
|
(defmacro ap-if (test-form &rest args)
|
|
`(let [[it ~test-form]] (if it ~@args)))
|
|
|
|
|
|
(defmacro ap-each [lst &rest body]
|
|
"Evaluate the body form for each element in the list."
|
|
`(for [it ~lst] ~@body))
|
|
|
|
|
|
(defmacro ap-each-while [lst form &rest body]
|
|
"Evalutate the body form for each element in the list while the
|
|
predicate form evaluates to True."
|
|
`(let [[p (lambda [it] ~form)]]
|
|
(for [it ~lst]
|
|
(if (p it)
|
|
~@body
|
|
(break)))))
|
|
|
|
|
|
(defmacro ap-map [form lst]
|
|
"Yield elements evaluated in the form for each element in the list."
|
|
`(let [[f (lambda [it] ~form)]]
|
|
(for [v ~lst]
|
|
(yield (f v)))))
|
|
|
|
|
|
(defmacro ap-map-when [predfn rep lst]
|
|
"Yield elements evaluated for each element in the list when the
|
|
predicate function returns True."
|
|
`(let [[f (lambda [it] ~rep)]]
|
|
(for [it ~lst]
|
|
(if (~predfn it)
|
|
(yield (f it))
|
|
(yield it)))))
|
|
|
|
|
|
(defmacro ap-filter [form lst]
|
|
"Yield elements returned when the predicate form evaluates to True."
|
|
`(let [[pred (lambda [it] ~form)]]
|
|
(for [val ~lst]
|
|
(if (pred val)
|
|
(yield val)))))
|
|
|
|
|
|
(defmacro ap-reject [form lst]
|
|
"Yield elements returned when the predicate form evaluates to False"
|
|
`(ap-filter (not ~form) ~lst))
|
|
|
|
|
|
(defmacro ap-dotimes [n &rest body]
|
|
"Execute body for side effects `n' times, with it bound from 0 to n-1"
|
|
(unless (numeric? n)
|
|
(raise (TypeError (.format "{0!r} is not a number" n))))
|
|
`(ap-each (range ~n) ~@body))
|
|
|
|
|
|
(defmacro ap-first [predfn lst]
|
|
"Yield the first element that passes `predfn`"
|
|
`(let [[n (gensym)]]
|
|
(ap-each ~lst (when ~predfn (setv n it) (break)))
|
|
n))
|
|
|
|
|
|
(defmacro ap-last [predfn lst]
|
|
"Yield the last element that passes `predfn`"
|
|
`(let [[n (gensym)]]
|
|
(ap-each ~lst (none? n)
|
|
(when ~predfn
|
|
(setv n it)))
|
|
n))
|
|
|
|
|
|
(defmacro ap-reduce [form lst &optional [initial-value None]]
|
|
"Anaphoric form of reduce, `acc' and `it' can be used for a form"
|
|
(if (none? initial-value)
|
|
`(let [[acc (car ~lst)]]
|
|
(ap-each (cdr ~lst) (setv acc ~form))
|
|
acc)
|
|
`(let [[acc ~initial-value]]
|
|
(ap-each ~lst (setv acc ~form))
|
|
acc)))
|