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(export '(and or not let* list* case cond append reverse macroexpand
otherwise unless when))
(%defmacro %defun args
(list '%fset
(list 'quote (car (cdr (car args))))
(cons '%lambda (cdr (cdr (car args))))))
(%defun list* args
(if (null (cdr args))
(car args)
(cons (car args)
(apply 'list* (cdr args)))))
(%defmacro let* args
(let ((form (car args)))
(let ((bindings (car (cdr form)))
(body (cdr (cdr form))))
(if (null bindings)
(list* 'let nil body)
(let ((first-binding (car bindings))
(rest (cdr bindings)))
(list 'let
(list first-binding)
(list* 'let* rest body)))))))
(%defmacro cond args
(let* ((form (car args))
(clauses (cdr form))
(clause (car clauses))
(rest (cdr clauses)))
(if (null clauses)
nil
(list 'if
(car clause)
(cons 'progn (cdr clause))
(cons 'cond rest)))))
(%defun not args
(if (null (car args)) t nil))
(%defun make-%defmacro*-body args
(let ((lambda-list (car args))
(lambda-list-name (car (cdr args)))
(body (car (cdr (cdr args)))))
(cond ((null lambda-list) body)
((not (listp lambda-list))
(list
(list* 'let
(list (list lambda-list lambda-list-name))
body)))
(t (let ((lambda-symbol (car lambda-list))
(rest-lambda-list (cdr lambda-list))
(rest-name (gensym)))
(list
(list* 'let
(list (list lambda-symbol
(list 'car lambda-list-name))
(list rest-name
(list 'cdr lambda-list-name)))
(make-%defmacro*-body (cdr lambda-list)
rest-name
body))))))))
(%defmacro %defmacro* args
(let* ((form (car args))
(real-args (cdr form)))
(let ((name (car real-args))
(lambda-list (car (cdr real-args)))
(body (cdr (cdr real-args)))
(macro-lambda-list-name (gensym))
(lambda-list-name (gensym)))
(list '%defmacro
name
macro-lambda-list-name
(list* 'let
(list (list lambda-list-name
(list 'cdr
(list 'car macro-lambda-list-name))))
(make-%defmacro*-body lambda-list lambda-list-name body))))))
(%defmacro %defun* args
(let* ((form (car args))
(real-args (cdr form)))
(let ((name (car real-args))
(lambda-list (car (cdr real-args)))
(body (cdr (cdr real-args)))
(lambda-list-name (gensym)))
(list* '%defun
name
lambda-list-name
(make-%defmacro*-body lambda-list lambda-list-name body)))))
(%defmacro* and expressions
(cond ((null expressions) t)
((null (cdr expressions)) (car expressions))
(t (list 'if
(car expressions)
(cons 'and (cdr expressions))
nil))))
(%defmacro* or expressions
(cond ((null expressions) nil)
((null (cdr expressions)) (car expressions))
(t (let ((expr-sym (gensym)))
(list 'let
(list (list expr-sym (car expressions)))
(list 'if
expr-sym
expr-sym
(cons 'or (cdr expressions))))))))
(%defun* %reverse-helper (list stack)
(if (null list)
stack
(%reverse-helper (cdr list) (cons (car list) stack))))
(%defun* reverse (list)
(%reverse-helper list nil))
(%defun* %append-helper (reversed-list1 list2)
(if (null reversed-list1)
list2
(%append-helper (cdr reversed-list1) (cons (car reversed-list1) list2))))
(%defun* %append-two-lists (list1 list2)
(%append-helper (reverse list1) list2))
(%defun* %append (lists)
(if (null (cdr lists))
(car lists)
(let ((first-list (car lists))
(second-list (car (cdr lists)))
(rest (cdr (cdr lists))))
(%append (list* (%append-two-lists first-list second-list) rest)))))
(%defun append lists
(%append lists))
(%defmacro* sys::quasiquote (object)
(if (not (consp object))
(list 'quote object)
(cond ((eq 'sys::unquote (car object)) (car (cdr object)))
((eq 'sys::quasiquote (car object)) (list 'quote object))
((and (consp (car object))
(eq 'sys::unquote-splicing (car (car object))))
(list 'append
(car (cdr (car object)))
(list 'sys::quasiquote (cdr object))))
(t (list 'cons
(list 'sys::quasiquote (car object))
(list 'sys::quasiquote (cdr object)))))))
(%defun* %member (item list)
(and list
(or (and (eq item (car list)) list)
(%member item (cdr list)))))
(%defmacro* case (object . clauses)
(let ((this-clause (car clauses))
(rest (cdr clauses))
(object-sym (gensym)))
(if (null clauses)
nil
(if (and (null rest)
(or (eq (car this-clause) t)
(eq (car this-clause) 'otherwise)))
`(progn ,@(cdr this-clause))
`(let ((,object-sym ,object))
(if ,(if (listp (car this-clause))
`(%member ,object-sym
(quote ,(car this-clause)))
`(eq ,object-sym
(quote ,(car this-clause))))
(progn ,@(cdr this-clause))
(case ,object-sym ,@rest)))))))
(%defun* list-eqp (list1 list2)
"Not really EQUALP (only works on trees of symbols)."
(if (and (consp list1) (consp list2))
(and (list-eqp (car list1) (car list2))
(list-eqp (cdr list1) (cdr list2)))
(eq list1 list2)))
(%defun* macroexpand (object . rest)
(let* ((env (if rest (car rest) nil))
(expansion-1 (macroexpand-1 object env))
(expansion-2 (macroexpand-1 expansion-1 env)))
(if (list-eqp expansion-1 expansion-2)
expansion-1
(macroexpand expansion-2))))
(%defmacro* unless (test . body)
`(if (not ,test) (progn ,@body) nil))
(%defmacro* when (test . body)
`(if ,test (progn ,@body) nil))
(%defmacro* %shadowing-export (symbol)
`(progn
(shadow ',symbol)
(unexport ',symbol (find-package :sys))
(unexport ',symbol (find-package :cl))
(export (intern (symbol-name ',symbol) (find-package :cl)))))
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