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-rw-r--r--third_party/lisp/alexandria/control-flow.lisp106
1 files changed, 0 insertions, 106 deletions
diff --git a/third_party/lisp/alexandria/control-flow.lisp b/third_party/lisp/alexandria/control-flow.lisp
deleted file mode 100644
index dd00df3e16..0000000000
--- a/third_party/lisp/alexandria/control-flow.lisp
+++ /dev/null
@@ -1,106 +0,0 @@
-(in-package :alexandria)
-
-(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))
-
-(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 T or OTHERWISE 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.")))
-
-(defmacro whichever (&rest possibilities &environment env)
-  "Evaluates exactly one of POSSIBILITIES, chosen at random."
-  (setf possibilities (mapcar (lambda (p) (macroexpand p env)) possibilities))
-  (if (every (lambda (p) (constantp p)) possibilities)
-      `(svref (load-time-value (vector ,@possibilities)) (random ,(length possibilities)))
-      (labels ((expand (possibilities position random-number)
-                 (if (null (cdr possibilities))
-                     (car possibilities)
-                     (let* ((length (length possibilities))
-                            (half (truncate length 2))
-                            (second-half (nthcdr half possibilities))
-                            (first-half (butlast possibilities (- length half))))
-                       `(if (< ,random-number ,(+ position half))
-                            ,(expand first-half position random-number)
-                            ,(expand second-half (+ position half) random-number))))))
-        (with-gensyms (random-number)
-          (let ((length (length possibilities)))
-            `(let ((,random-number (random ,length)))
-               ,(expand possibilities 0 random-number)))))))
-
-(defmacro xor (&rest datums)
-  "Evaluates its arguments one at a time, from left to right. If more than one
-argument evaluates to a true value no further DATUMS are evaluated, and NIL is
-returned as both primary and secondary value. If exactly one argument
-evaluates to true, its value is returned as the primary value after all the
-arguments have been evaluated, and T is returned as the secondary value. If no
-arguments evaluate to true NIL is retuned as primary, and T as secondary
-value."
-  (with-gensyms (xor tmp true)
-    `(let (,tmp ,true)
-       (block ,xor
-         ,@(mapcar (lambda (datum)
-                     `(if (setf ,tmp ,datum)
-                          (if ,true
-                              (return-from ,xor (values nil nil))
-                              (setf ,true ,tmp))))
-                   datums)
-         (return-from ,xor (values ,true t))))))
-
-(defmacro nth-value-or (nth-value &body forms)
-  "Evaluates FORM arguments one at a time, until the NTH-VALUE returned by one
-of the forms is true. It then returns all the values returned by evaluating
-that form. If none of the forms return a true nth value, this form returns
-NIL."
-  (once-only (nth-value)
-    (with-gensyms (values)
-      `(let ((,values (multiple-value-list ,(first forms))))
-         (if (nth ,nth-value ,values)
-             (values-list ,values)
-             ,(if (rest forms)
-                  `(nth-value-or ,nth-value ,@(rest forms))
-                  nil))))))
-
-(defmacro multiple-value-prog2 (first-form second-form &body forms)
-  "Evaluates FIRST-FORM, then SECOND-FORM, and then FORMS. Yields as its value
-all the value returned by SECOND-FORM."
-  `(progn ,first-form (multiple-value-prog1 ,second-form ,@forms)))