| author |
Steve Losh <steve@stevelosh.com> |
| date |
Mon, 13 Feb 2017 13:20:22 +0000 |
| parents |
55e8aef75bee |
| children |
7c082c0289d5 |
;;;; This file was automatically generated by Quickutil.
;;;; See http://quickutil.org for details.
;;;; To regenerate:
;;;; (qtlc:save-utils-as "quickutils.lisp" :utilities '(:CURRY :DEFINE-CONSTANT :ENSURE-BOOLEAN :N-GRAMS :RANGE :RCURRY :SWITCH :WITH-GENSYMS) :ensure-package T :package "EULER.QUICKUTILS")
(eval-when (:compile-toplevel :load-toplevel :execute)
(unless (find-package "EULER.QUICKUTILS")
(defpackage "EULER.QUICKUTILS"
(:documentation "Package that contains Quickutil utility functions.")
(:use #:cl))))
(in-package "EULER.QUICKUTILS")
(when (boundp '*utilities*)
(setf *utilities* (union *utilities* '(:MAKE-GENSYM-LIST :ENSURE-FUNCTION
:CURRY :DEFINE-CONSTANT
:ENSURE-BOOLEAN :TAKE :N-GRAMS :RANGE
:RCURRY :STRING-DESIGNATOR
:WITH-GENSYMS :EXTRACT-FUNCTION-NAME
:SWITCH))))
(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 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))))
(defun ensure-boolean (x)
"Convert `x` into a Boolean value."
(and x t))
(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))))))
(defun range (start end &key (step 1) (key 'identity))
"Return the list of numbers `n` such that `start <= n < end` and
`n = start + k*step` for suitable integers `k`. If a function `key` is
provided, then apply it to each number."
(assert (<= start end))
(loop :for i :from start :below end :by step :collecting (funcall key i)))
(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)))))
(deftype string-designator ()
"A string designator type. A string designator is either a string, a symbol,
or a character."
`(or symbol string character))
(eval-when (:compile-toplevel :load-toplevel :execute)
(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
(eval-when (:compile-toplevel :load-toplevel :execute)
(defun extract-function-name (spec)
"Useful for macros that want to mimic the functional interface for functions
like `#'eq` and `'eq`."
(if (and (consp spec)
(member (first spec) '(quote function)))
(second spec)
spec))
) ; eval-when
(eval-when (:compile-toplevel :load-toplevel :execute)
(defun generate-switch-body (whole object clauses test key &optional default)
(with-gensyms (value)
(setf test (extract-function-name test))
(setf key (extract-function-name key))
(when (and (consp default)
(member (first default) '(error cerror)))
(setf default `(,@default "No keys match in SWITCH. Testing against ~S with ~S."
,value ',test)))
`(let ((,value (,key ,object)))
(cond ,@(mapcar (lambda (clause)
(if (member (first clause) '(t otherwise))
(progn
(when default
(error "Multiple default clauses or illegal use of a default clause in ~S."
whole))
(setf default `(progn ,@(rest clause)))
'(()))
(destructuring-bind (key-form &body forms) clause
`((,test ,value ,key-form)
,@forms))))
clauses)
(t ,default))))))
(defmacro switch (&whole whole (object &key (test 'eql) (key 'identity))
&body clauses)
"Evaluates first matching clause, returning its values, or evaluates and
returns the values of `default` if no keys match."
(generate-switch-body whole object clauses test key))
(defmacro eswitch (&whole whole (object &key (test 'eql) (key 'identity))
&body clauses)
"Like `switch`, but signals an error if no key matches."
(generate-switch-body whole object clauses test key '(error)))
(defmacro cswitch (&whole whole (object &key (test 'eql) (key 'identity))
&body clauses)
"Like `switch`, but signals a continuable error if no key matches."
(generate-switch-body whole object clauses test key '(cerror "Return NIL from CSWITCH.")))
(eval-when (:compile-toplevel :load-toplevel :execute)
(export '(curry define-constant ensure-boolean n-grams range rcurry switch
eswitch cswitch with-gensyms with-unique-names)))
;;;; END OF quickutils.lisp ;;;;