| author |
Steve Losh <steve@stevelosh.com> |
| date |
Wed, 07 Dec 2016 15:14:38 -0500 |
| parents |
09407f2a9764 |
| children |
de58fc1af1e5 |
;;;; This file was automatically generated by Quickutil.
;;;; See http://quickutil.org for details.
;;;; To regenerate:
;;;; (qtlc:save-utils-as "quickutils.lisp" :utilities '(:COMPOSE :CURRY :DEFINE-CONSTANT :ENSURE-GETHASH :ENSURE-LIST :HASH-TABLE-ALIST :HASH-TABLE-KEYS :HASH-TABLE-PLIST :HASH-TABLE-VALUES :N-GRAMS :ONCE-ONLY :RCURRY :READ-FILE-INTO-STRING :REQUIRED-ARGUMENT :RIFFLE :SUBDIVIDE :SYMB :TREE-COLLECT :WITH-GENSYMS) :ensure-package T :package "SAND.QUICKUTILS")
(eval-when (:compile-toplevel :load-toplevel :execute)
(unless (find-package "SAND.QUICKUTILS")
(defpackage "SAND.QUICKUTILS"
(:documentation "Package that contains Quickutil utility functions.")
(:use #:cl))))
(in-package "SAND.QUICKUTILS")
(when (boundp '*utilities*)
(setf *utilities* (union *utilities* '(:MAKE-GENSYM-LIST :ENSURE-FUNCTION
:COMPOSE :CURRY :DEFINE-CONSTANT
:ENSURE-GETHASH :ENSURE-LIST
:HASH-TABLE-ALIST :MAPHASH-KEYS
:HASH-TABLE-KEYS :HASH-TABLE-PLIST
:MAPHASH-VALUES :HASH-TABLE-VALUES
:TAKE :N-GRAMS :ONCE-ONLY :RCURRY
:WITH-OPEN-FILE* :WITH-INPUT-FROM-FILE
:READ-FILE-INTO-STRING
:REQUIRED-ARGUMENT :RIFFLE :SUBDIVIDE
:MKSTR :SYMB :TREE-COLLECT
:STRING-DESIGNATOR :WITH-GENSYMS))))
(eval-when (:compile-toplevel :load-toplevel :execute)
(defun make-gensym-list (length &optional (x "G"))
"Returns a list of `length` gensyms, each generated as if with a call to `make-gensym`,
using the second (optional, defaulting to `\"G\"`) argument."
(let ((g (if (typep x '(integer 0)) x (string x))))
(loop repeat length
collect (gensym g))))
) ; eval-when
(eval-when (:compile-toplevel :load-toplevel :execute)
;;; To propagate return type and allow the compiler to eliminate the IF when
;;; it is known if the argument is function or not.
(declaim (inline ensure-function))
(declaim (ftype (function (t) (values function &optional))
ensure-function))
(defun ensure-function (function-designator)
"Returns the function designated by `function-designator`:
if `function-designator` is a function, it is returned, otherwise
it must be a function name and its `fdefinition` is returned."
(if (functionp function-designator)
function-designator
(fdefinition function-designator)))
) ; eval-when
(defun compose (function &rest more-functions)
"Returns a function composed of `function` and `more-functions` that applies its ;
arguments to to each in turn, starting from the rightmost of `more-functions`,
and then calling the next one with the primary value of the last."
(declare (optimize (speed 3) (safety 1) (debug 1)))
(reduce (lambda (f g)
(let ((f (ensure-function f))
(g (ensure-function g)))
(lambda (&rest arguments)
(declare (dynamic-extent arguments))
(funcall f (apply g arguments)))))
more-functions
:initial-value function))
(define-compiler-macro compose (function &rest more-functions)
(labels ((compose-1 (funs)
(if (cdr funs)
`(funcall ,(car funs) ,(compose-1 (cdr funs)))
`(apply ,(car funs) arguments))))
(let* ((args (cons function more-functions))
(funs (make-gensym-list (length args) "COMPOSE")))
`(let ,(loop for f in funs for arg in args
collect `(,f (ensure-function ,arg)))
(declare (optimize (speed 3) (safety 1) (debug 1)))
(lambda (&rest arguments)
(declare (dynamic-extent arguments))
,(compose-1 funs))))))
(defun curry (function &rest arguments)
"Returns a function that applies `arguments` and the arguments
it is called with to `function`."
(declare (optimize (speed 3) (safety 1) (debug 1)))
(let ((fn (ensure-function function)))
(lambda (&rest more)
(declare (dynamic-extent more))
;; Using M-V-C we don't need to append the arguments.
(multiple-value-call fn (values-list arguments) (values-list more)))))
(define-compiler-macro curry (function &rest arguments)
(let ((curries (make-gensym-list (length arguments) "CURRY"))
(fun (gensym "FUN")))
`(let ((,fun (ensure-function ,function))
,@(mapcar #'list curries arguments))
(declare (optimize (speed 3) (safety 1) (debug 1)))
(lambda (&rest more)
(apply ,fun ,@curries more)))))
(defun %reevaluate-constant (name value test)
(if (not (boundp name))
value
(let ((old (symbol-value name))
(new value))
(if (not (constantp name))
(prog1 new
(cerror "Try to redefine the variable as a constant."
"~@<~S is an already bound non-constant variable ~
whose value is ~S.~:@>" name old))
(if (funcall test old new)
old
(restart-case
(error "~@<~S is an already defined constant whose value ~
~S is not equal to the provided initial value ~S ~
under ~S.~:@>" name old new test)
(ignore ()
:report "Retain the current value."
old)
(continue ()
:report "Try to redefine the constant."
new)))))))
(defmacro define-constant (name initial-value &key (test ''eql) documentation)
"Ensures that the global variable named by `name` is a constant with a value
that is equal under `test` to the result of evaluating `initial-value`. `test` is a
function designator that defaults to `eql`. If `documentation` is given, it
becomes the documentation string of the constant.
Signals an error if `name` is already a bound non-constant variable.
Signals an error if `name` is already a constant variable whose value is not
equal under `test` to result of evaluating `initial-value`."
`(defconstant ,name (%reevaluate-constant ',name ,initial-value ,test)
,@(when documentation `(,documentation))))
(defmacro ensure-gethash (key hash-table &optional default)
"Like `gethash`, but if `key` is not found in the `hash-table` saves the `default`
under key before returning it. Secondary return value is true if key was
already in the table."
`(multiple-value-bind (value ok) (gethash ,key ,hash-table)
(if ok
(values value ok)
(values (setf (gethash ,key ,hash-table) ,default) nil))))
(defun ensure-list (list)
"If `list` is a list, it is returned. Otherwise returns the list designated by `list`."
(if (listp list)
list
(list list)))
(defun hash-table-alist (table)
"Returns an association list containing the keys and values of hash table
`table`."
(let ((alist nil))
(maphash (lambda (k v)
(push (cons k v) alist))
table)
alist))
(declaim (inline maphash-keys))
(defun maphash-keys (function table)
"Like `maphash`, but calls `function` with each key in the hash table `table`."
(maphash (lambda (k v)
(declare (ignore v))
(funcall function k))
table))
(defun hash-table-keys (table)
"Returns a list containing the keys of hash table `table`."
(let ((keys nil))
(maphash-keys (lambda (k)
(push k keys))
table)
keys))
(defun hash-table-plist (table)
"Returns a property list containing the keys and values of hash table
`table`."
(let ((plist nil))
(maphash (lambda (k v)
(setf plist (list* k v plist)))
table)
plist))
(declaim (inline maphash-values))
(defun maphash-values (function table)
"Like `maphash`, but calls `function` with each value in the hash table `table`."
(maphash (lambda (k v)
(declare (ignore k))
(funcall function v))
table))
(defun hash-table-values (table)
"Returns a list containing the values of hash table `table`."
(let ((values nil))
(maphash-values (lambda (v)
(push v values))
table)
values))
(defun take (n sequence)
"Take the first `n` elements from `sequence`."
(subseq sequence 0 n))
(defun n-grams (n sequence)
"Find all `n`-grams of the sequence `sequence`."
(assert (and (plusp n)
(<= n (length sequence))))
(etypecase sequence
;; Lists
(list (loop :repeat (1+ (- (length sequence) n))
:for seq :on sequence
:collect (take n seq)))
;; General sequences
(sequence (loop :for i :to (- (length sequence) n)
:collect (subseq sequence i (+ i n))))))
(defmacro once-only (specs &body forms)
"Evaluates `forms` with symbols specified in `specs` rebound to temporary
variables, ensuring that each initform is evaluated only once.
Each of `specs` must either be a symbol naming the variable to be rebound, or of
the form:
(symbol initform)
Bare symbols in `specs` are equivalent to
(symbol symbol)
Example:
(defmacro cons1 (x) (once-only (x) `(cons ,x ,x)))
(let ((y 0)) (cons1 (incf y))) => (1 . 1)"
(let ((gensyms (make-gensym-list (length specs) "ONCE-ONLY"))
(names-and-forms (mapcar (lambda (spec)
(etypecase spec
(list
(destructuring-bind (name form) spec
(cons name form)))
(symbol
(cons spec spec))))
specs)))
;; bind in user-macro
`(let ,(mapcar (lambda (g n) (list g `(gensym ,(string (car n)))))
gensyms names-and-forms)
;; bind in final expansion
`(let (,,@(mapcar (lambda (g n)
``(,,g ,,(cdr n)))
gensyms names-and-forms))
;; bind in user-macro
,(let ,(mapcar (lambda (n g) (list (car n) g))
names-and-forms gensyms)
,@forms)))))
(defun rcurry (function &rest arguments)
"Returns a function that applies the arguments it is called
with and `arguments` to `function`."
(declare (optimize (speed 3) (safety 1) (debug 1)))
(let ((fn (ensure-function function)))
(lambda (&rest more)
(declare (dynamic-extent more))
(multiple-value-call fn (values-list more) (values-list arguments)))))
(defmacro with-open-file* ((stream filespec &key direction element-type
if-exists if-does-not-exist external-format)
&body body)
"Just like `with-open-file`, but `nil` values in the keyword arguments mean to use
the default value specified for `open`."
(once-only (direction element-type if-exists if-does-not-exist external-format)
`(with-open-stream
(,stream (apply #'open ,filespec
(append
(when ,direction
(list :direction ,direction))
(when ,element-type
(list :element-type ,element-type))
(when ,if-exists
(list :if-exists ,if-exists))
(when ,if-does-not-exist
(list :if-does-not-exist ,if-does-not-exist))
(when ,external-format
(list :external-format ,external-format)))))
,@body)))
(defmacro with-input-from-file ((stream-name file-name &rest args
&key (direction nil direction-p)
&allow-other-keys)
&body body)
"Evaluate `body` with `stream-name` to an input stream on the file
`file-name`. `args` is sent as is to the call to `open` except `external-format`,
which is only sent to `with-open-file` when it's not `nil`."
(declare (ignore direction))
(when direction-p
(error "Can't specifiy :DIRECTION for WITH-INPUT-FROM-FILE."))
`(with-open-file* (,stream-name ,file-name :direction :input ,@args)
,@body))
(defun read-file-into-string (pathname &key (buffer-size 4096) external-format)
"Return the contents of the file denoted by `pathname` as a fresh string.
The `external-format` parameter will be passed directly to `with-open-file`
unless it's `nil`, which means the system default."
(with-input-from-file
(file-stream pathname :external-format external-format)
(let ((*print-pretty* nil))
(with-output-to-string (datum)
(let ((buffer (make-array buffer-size :element-type 'character)))
(loop
:for bytes-read = (read-sequence buffer file-stream)
:do (write-sequence buffer datum :start 0 :end bytes-read)
:while (= bytes-read buffer-size)))))))
(defun required-argument (&optional name)
"Signals an error for a missing argument of `name`. Intended for
use as an initialization form for structure and class-slots, and
a default value for required keyword arguments."
(error "Required argument ~@[~S ~]missing." name))
(defun riffle (list obj)
"Insert the item `obj` in between each element of `list`."
(loop :for (x . xs) :on list
:collect x
:when xs
:collect obj))
(defun subdivide (sequence chunk-size)
"Split `sequence` into subsequences of size `chunk-size`."
(check-type sequence sequence)
(check-type chunk-size (integer 1))
(etypecase sequence
;; Since lists have O(N) access time, we iterate through manually,
;; collecting each chunk as we pass through it. Using SUBSEQ would
;; be O(N^2).
(list (loop :while sequence
:collect
(loop :repeat chunk-size
:while sequence
:collect (pop sequence))))
;; For other sequences like strings or arrays, we can simply chunk
;; by repeated SUBSEQs.
(sequence (loop :with len := (length sequence)
:for i :below len :by chunk-size
:collect (subseq sequence i (min len (+ chunk-size i)))))))
(defun mkstr (&rest args)
"Receives any number of objects (string, symbol, keyword, char, number), extracts all printed representations, and concatenates them all into one string.
Extracted from _On Lisp_, chapter 4."
(with-output-to-string (s)
(dolist (a args) (princ a s))))
(defun symb (&rest args)
"Receives any number of objects, concatenates all into one string with `#'mkstr` and converts them to symbol.
Extracted from _On Lisp_, chapter 4.
See also: `symbolicate`"
(values (intern (apply #'mkstr args))))
(defun tree-collect (predicate tree)
"Returns a list of every node in the `tree` that satisfies the `predicate`. If there are any improper lists in the tree, the `predicate` is also applied to their dotted elements."
(let ((sentinel (gensym)))
(flet ((my-cdr (obj)
(cond ((consp obj)
(let ((result (cdr obj)))
(if (listp result)
result
(list result sentinel))))
(t
(list sentinel)))))
(loop :for (item . rest) :on tree :by #'my-cdr
:until (eq item sentinel)
:if (funcall predicate item) collect item
:else
:if (listp item)
:append (tree-collect predicate item)))))
(deftype string-designator ()
"A string designator type. A string designator is either a string, a symbol,
or a character."
`(or symbol string character))
(defmacro with-gensyms (names &body forms)
"Binds each variable named by a symbol in `names` to a unique symbol around
`forms`. Each of `names` must either be either a symbol, or of the form:
(symbol string-designator)
Bare symbols appearing in `names` are equivalent to:
(symbol symbol)
The string-designator is used as the argument to `gensym` when constructing the
unique symbol the named variable will be bound to."
`(let ,(mapcar (lambda (name)
(multiple-value-bind (symbol string)
(etypecase name
(symbol
(values name (symbol-name name)))
((cons symbol (cons string-designator null))
(values (first name) (string (second name)))))
`(,symbol (gensym ,string))))
names)
,@forms))
(defmacro with-unique-names (names &body forms)
"Binds each variable named by a symbol in `names` to a unique symbol around
`forms`. Each of `names` must either be either a symbol, or of the form:
(symbol string-designator)
Bare symbols appearing in `names` are equivalent to:
(symbol symbol)
The string-designator is used as the argument to `gensym` when constructing the
unique symbol the named variable will be bound to."
`(with-gensyms ,names ,@forms))
(eval-when (:compile-toplevel :load-toplevel :execute)
(export '(compose curry define-constant ensure-gethash ensure-list
hash-table-alist hash-table-keys hash-table-plist hash-table-values
n-grams once-only rcurry read-file-into-string required-argument
riffle subdivide symb tree-collect with-gensyms with-unique-names)))
;;;; END OF quickutils.lisp ;;;;