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571 lines
21 KiB
Common Lisp
571 lines
21 KiB
Common Lisp
;;; **********************************************************************
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;;; Copyright (C) 2006 Rick Taube
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;;; This program is free software; you can redistribute it and/or
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;;; modify it under the terms of the Lisp Lesser Gnu Public License.
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;;; See http://www.cliki.net/LLGPL for the text of this agreement.
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;;; **********************************************************************
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;;; $Revision: 1.2 $
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;;; $Date: 2009-03-05 17:42:25 $
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;; DATA STRUCTURES AND ALGORITHMS (for sal.lsp and parse.lsp)
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;;
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;; TOKENIZE converts source language (a string) into a list of tokens
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;; each token is represented as follows:
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;; (:TOKEN <type> <string> <start> <info> <lisp>)
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;; where <type> is one of:
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;; :id -- an identifier
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;; :lp -- left paren
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;; :rp -- right paren
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;; :+, etc. -- operators
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;; :int -- an integer
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;; :float -- a float
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;; :print, etc. -- a reserved word
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;; <string> is the source string for the token
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;; <start> is the column of the string
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;; <info> and <lisp> are ??
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;; Tokenize uses a list of reserved words extracted from terminals in
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;; the grammar. Each reserved word has an associated token type, but
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;; all other identifiers are simply of type :ID.
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;;
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;; *** WHY REWRITE THE ORIGINAL PARSER? ***
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;; Originally, the code interpreted a grammar using a recursive pattern
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;; matcher, but XLISP does not have a huge stack and there were
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;; stack overflow problems because even relatively small expressions
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;; went through a very deep nesting of productions. E.g.
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;; "print note(between(30,odds(.5, 60, 90)))" 0 t nil))" was at recursion
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;; level 46 when the stack overflowed. The stack depth is 2000 or 4000,
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;; but all locals and parameters get pushed here, so since PARSE is the
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;; recursive function and it has lots of parameters and locals, it appears
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;; to use 80 elements in the stack per call.
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;; *** END ***
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;;
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;; The grammar for the recursive descent parser:
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;; note: [ <x> ] means optional <x>, <x>* means 0 or more of <x>
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;;
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;; <number> = <int> | <float>
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;; <atom> = <int> | <float> | <id> | <bool>
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;; <list> = { <elt>* }
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;; <elt> = <atom> | <list> | <string>
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;; <aref> = <id> <lb> <pargs> <rb>
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;; <ifexpr> = ? "(" <sexpr> , <sexpr> [ , <sexpr> ] ")"
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;; <funcall> = <id> <funargs>
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;; <funargs> = "(" [ <args> ] ")"
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;; <args> = <arg> [ , <arg> ]*
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;; <arg> = <sexpr> | <key> <sexpr>
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;; <op> = + | - | "*" | / | % | ^ | = | != |
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;; "<" | ">" | "<=" | ">=" | ~= | ! | & | "|"
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;; <mexpr> = <term> [ <op> <term> ]*
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;; <term> = <-> <term> | <!> <term> | "(" <mexpr> ")" |
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;; <ifexpr> | <funcall> | <aref> | <atom> | <list> | <string>
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;; <sexpr> = <mexpr> | <object> | class
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;; <top> = <command> | <block> | <conditional> | <assignment> | <loop> | <exec>
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;; <exec> = exec <sexpr>
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;; <command> = <define-cmd> | <file-cmd> | <output>
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;; <define-cmd> = define <declaration>
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;; <declaration> = <vardecl> | <fundecl>
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;; <vardecl> = variable <bindings>
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;; <bindings> = <bind> [ , <bind> ]*
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;; <bind> = <id> [ <=> <sexpr> ]
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;; <fundecl> = <function> <id> "(" [ <parms> ] ")" <statement>
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;; <parms> = <parm> [ , <parm> ]*
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;; this is new: key: expression for keyword parameter
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;; <parm> = <id> | <key> [ <sexpr> ]
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;; <statement> = <block> | <conditional> | <assignment> |
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;; <output-stmt> <loop-stmt> <return-from> | <exec>
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;; <block> = begin [ with <bindings> [ <statement> ]* end
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;; <conditional> = if <sexpr> then [ <statement> ] [ else <statement> ] |
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;; when <sexpr> <statement> | unless <sexpr> <statement>
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;; <assignment> = set <assign> [ , <assign> ]*
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;; <assign> = ( <aref> | <id> ) <assigner> <sexpr>
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;; <assigner> = = | += | *= | &= | @= | ^= | "<=" | ">="
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;; <file-cmd> = <load-cmd> | chdir <pathref> |
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;; system <pathref> | play <sexpr>
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;; (note: system was removed)
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;; <load-cmd> = load <pathref> [ , <key> <sexpr> ]*
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;; <pathref> = <string> | <id>
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;; <output-stmt> = print <sexpr> [ , <sexpr> ]* |
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;; output <sexpr>
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;; <loop-stmt> = loop [ with <bindings> ] [ <stepping> ]*
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;; [ <termination> ]* [ <statement> ]+
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;; [ finally <statement> ] end
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;; <stepping> = repeat <sexpr> |
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;; for <id> = <sexpr> [ then <sexpr> ] |
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;; for <id> in <sexpr> |
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;; for <id> over <sexpr> [ by <sexpr> ] |
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;; for <id> [ from <sexpr> ]
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;; [ ( below | to | above | downto ) <sexpr> ]
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;; [ by <sexpr> ] |
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;; <termination> = while <sexpr> | until <sexpr>
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;; <return-from> = return <sexpr>
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;(in-package cm)
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; (progn (cd "/Lisp/sal/") (load "parse.lisp") (load "sal.lisp"))
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(setfn defconstant setf)
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(setfn defparameter setf)
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(setfn defmethod defun)
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(setfn defvar setf)
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(setfn values list)
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(if (not (boundp '*sal-secondary-prompt*))
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(setf *sal-secondary-prompt* t))
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(if (not (boundp '*sal-xlispbreak*))
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(setf *sal-xlispbreak* nil))
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(defun sal-trace-enter (fn &optional argvals argnames)
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(push (list fn *sal-line* argvals argnames) *sal-call-stack*))
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(defun sal-trace-exit ()
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(setf *sal-line* (second (car *sal-call-stack*)))
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(pop *sal-call-stack*))
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;; SAL-RETURN-FROM is generated by Sal compiler and
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;; performs a return as well as a sal-trace-exit()
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;;
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(defmacro sal-return-from (fn val)
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`(prog ((sal:return-value ,val))
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(setf *sal-line* (second (car *sal-call-stack*)))
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(pop *sal-call-stack*)
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(return-from ,fn sal:return-value)))
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(setf *sal-traceback* t)
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(defun sal-traceback (&optional (file t)
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&aux comma name names line)
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(format file "Call traceback:~%")
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(setf line *sal-line*)
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(dolist (frame *sal-call-stack*)
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(setf comma "")
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(format file " ~A" (car frame))
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(cond ((symbolp (car frame))
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(format file "(")
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(setf names (cadddr frame))
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(dolist (arg (caddr frame))
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(setf name (car names))
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(format file "~A~% ~A = ~A" comma name arg)
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(setf names (cdr names))
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(setf comma ","))
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(format file ") at line ~A~%" line)
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(setf line (second frame)))
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(t
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(format file "~%")))))
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'(defmacro defgrammer (sym rules &rest args)
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`(defparameter ,sym
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(make-grammer :rules ',rules ,@args)))
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'(defun make-grammer (&key rules literals)
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(let ((g (list 'a-grammer rules literals)))
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(grammer-initialize g)
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g))
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'(defmethod grammer-initialize (obj)
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(let (xlist)
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;; each literal is (:name "name")
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(cond ((grammer-literals obj)
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(dolist (x (grammer-literals obj))
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(cond ((consp x)
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(push x xlist))
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(t
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(push (list (string->keyword (string-upcase (string x)))
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(string-downcase (string x)))
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xlist)))))
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(t
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(dolist (x (grammer-rules obj))
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(cond ((terminal-rule? x)
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(push (list (car x)
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(string-downcase (subseq (string (car x)) 1)))
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xlist))))))
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(set-grammer-literals obj (reverse xlist))))
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'(setfn grammer-rules cadr)
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'(setfn grammer-literals caddr)
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'(defun set-grammer-literals (obj val)
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(setf (car (cddr obj)) val))
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'(defun is-grammer (obj) (and (consp obj) (eq (car obj) 'a-grammer)))
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(defun string->keyword (str)
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(intern (strcat ":" (string-upcase str))))
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(defun terminal-rule? (rule)
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(or (null (cdr rule)) (not (cadr rule))))
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(load "sal-parse.lsp" :verbose nil)
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(defparameter *sal-print-list* t)
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(defun sal-printer (x &key (stream *standard-output*) (add-space t))
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(let ((*print-case* ':downcase))
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(cond ((and (consp x) *sal-print-list*)
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(write-char #\{ stream)
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(do ((items x (cdr items)))
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((null items))
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(sal-printer (car items) :stream stream
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:add-space (cdr items))
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(cond ((cdr items)
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(cond ((not (consp (cdr items)))
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(princ "<list not well-formed> " stream)
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(sal-printer (cdr items) :stream stream :add-space nil)
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(setf items nil))))))
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(write-char #\} stream))
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((not x) (princ "#f" stream) )
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((eq x t) (princ "#t" stream))
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(t (princ x stream)))
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(if add-space (write-char #\space stream))))
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(defparameter *sal-printer* #'sal-printer)
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(defun sal-message (string &rest args)
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(format t "~&; ")
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(apply #'format t string args))
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(defun sal-print (&rest args)
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(terpri)
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(mapc *sal-printer* args)
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(values))
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(defmacro keyword (sym)
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`(str-to-keyword (symbol-name ',sym)))
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(defun plus (&rest nums)
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(apply #'+ nums))
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(defun minus (num &rest nums)
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(apply #'- num nums))
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(defun times (&rest nums)
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(apply #'* nums))
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(defun divide (num &rest nums)
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(apply #'/ num nums))
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;; implementation of infix "!=" operator
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(defun not-eql (x y)
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(not (eql x y)))
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; dir "*.*
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; chdir
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; load "rts.sys"
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(defun sal-chdir ( dir)
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(cd (expand-path-name dir))
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(sal-message "Directory: ~A" (pwd))
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(values))
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;;; sigh, not all lisps support ~/ directory components.
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(defun expand-path-name (path &optional absolute?)
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(let ((dir (pathname-directory path)))
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(flet ((curdir ()
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(truename
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(make-pathname :directory
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(pathname-directory
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*default-pathname-defaults*)))))
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(cond ((null dir)
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(if (equal path "~")
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(namestring (user-homedir-pathname))
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(if absolute?
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(namestring (merge-pathnames path (curdir)))
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(namestring path))))
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((eql (car dir) ':absolute)
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(namestring path))
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(t
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(let* ((tok (second dir))
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(len (length tok)))
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(if (char= (char tok 0) #\~)
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(let ((uhd (pathname-directory (user-homedir-pathname))))
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(if (= len 1)
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(namestring
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(make-pathname :directory (append uhd (cddr dir))
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:defaults path))
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(namestring
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(make-pathname :directory
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(append (butlast uhd)
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(list (subseq tok 1))
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(cddr dir))
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:defaults path))))
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(if absolute?
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(namestring (merge-pathnames path (curdir)))
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(namestring path)))))))))
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(defun sal-load (filename &key (verbose t) print)
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(progv '(*sal-input-file-name*) (list filename)
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(prog (file extended-name)
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;; first try to load exact name
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(cond ((setf file (open filename))
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(close file) ;; found it: close it and load it
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(return (generic-loader filename verbose print))))
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;; try to load name with ".sal" or ".lsp"
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(cond ((string-search "." filename) ; already has extension
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nil) ; don't try to add another extension
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((setf file (open (strcat filename ".sal")))
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(close file)
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(return (sal-loader (strcat filename ".sal")
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:verbose verbose :print print)))
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((setf file (open (strcat filename ".lsp")))
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(close file)
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(return (lisp-loader filename :verbose verbose :print print))))
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;; search for file as is or with ".lsp" on path
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(setf fullpath (find-in-xlisp-path filename))
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(cond ((and (not fullpath) ; search for file.sal on path
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(not (string-search "." filename))) ; no extension yet
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(setf fullpath (find-in-xlisp-path (strcat filename ".sal")))))
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(cond ((null fullpath)
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(format t "sal-load: could not find ~A~%" filename))
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(t
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(return (generic-loader filename verbose print)))))))
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;; GENERIC-LOADER -- load a sal or lsp file based on extension
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;;
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;; assumes that file exists, and if no .sal extension, type is Lisp
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;;
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(defun generic-loader (fullpath verbose print)
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(cond ((has-extension fullpath ".sal")
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(sal-loader fullpath :verbose verbose :print print))
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(t
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(lisp-loader fullpath :verbose verbose :print print))))
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#|
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(defun sal-load (filename &key (verbose t) print)
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(progv '(*sal-input-file-name*) (list filename)
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(let (file extended-name)
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(cond ((has-extension filename ".sal")
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(sal-loader filename :verbose verbose :print print))
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((has-extension filename ".lsp")
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(lisp-load filename :verbose verbose :print print))
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;; see if we can just open the exact filename and load it
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((setf file (open filename))
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(close file)
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(lisp-load filename :verbose verbose :print print))
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;; if not, then try loading file.sal and file.lsp
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((setf file (open (setf *sal-input-file-name*
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(strcat filename ".sal"))))
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(close file)
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(sal-loader *sal-input-file-name* :verbose verbose :print print))
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((setf file (open (setf *sal-input-file-name*
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(strcat filename ".lsp"))))
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(close file)
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(lisp-load *sal-input-file-name* :verbose verbose :print print))
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(t
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(format t "sal-load: could not find ~A~%" filename))))))
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|#
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(defun lisp-loader (filename &key (verbose t) print)
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(if (load filename :verbose verbose :print print)
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nil ; be quiet if things work ok
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(format t "error loading lisp file ~A~%" filename)))
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(defun has-extension (filename ext)
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(let ((loc (string-search ext filename
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:start (max 0 (- (length filename)
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(length ext))))))
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(not (null loc)))) ; coerce to t or nil
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(defmacro sal-at (s x) (list 'at x s))
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(defmacro sal-at-abs (s x) (list 'at-abs x s))
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(defmacro sal-stretch (s x) (list 'stretch x s))
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(defmacro sal-stretch-abs (s x) (list 'stretch-abs x s))
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;; splice every pair of lines
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(defun strcat-pairs (lines)
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(let (rslt)
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(while lines
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(push (strcat (car lines) (cadr lines)) rslt)
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(setf lines (cddr lines)))
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(reverse rslt)))
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(defun strcat-list (lines)
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;; like (apply 'strcat lines), but does not use a lot of stack
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;; When there are too many lines, XLISP will overflow the stack
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;; because args go on the stack.
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(let (r)
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(while (> (setf len (length lines)) 1)
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(if (oddp len) (setf lines (cons "" lines)))
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(setf lines (strcat-pairs lines)))
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; if an empty list, return "", else list has one string: return it
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(if (null lines) "" (car lines))))
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(defun sal-loader (filename &key verbose print)
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(let ((input "") (file (open filename)) line lines)
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(cond (file
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(push filename *loadingfiles*)
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(while (setf line (read-line file))
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(push line lines)
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(push "\n" lines))
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(close file)
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(setf input (strcat-list (reverse lines)))
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(sal-trace-enter (strcat "Loading " filename))
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(sal-compile input t t filename)
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(pop *loadingfiles*)
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(sal-trace-exit))
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(t
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(format t "error loading SAL file ~A~%" filename)))))
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; SYSTEM command is not implemented
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;(defun sal-system (sys &rest pairs)
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; (apply #'use-system sys pairs))
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(defun load-sal-file (file)
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(with-open-file (f file :direction :input)
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(let ((input (make-array '(512) :element-type 'character
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:fill-pointer 0 :adjustable t)))
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(loop with flag
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for char = (read-char f nil ':eof)
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until (or flag (eql char ':eof))
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do
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(when (char= char #\;)
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(loop do (setq char (read-char f nil :eof))
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until (or (eql char :eof)
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(char= char #\newline))))
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(unless (eql char ':eof)
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(vector-push-extend char input)))
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(sal input :pattern :command-sequence))))
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(defmacro sal-play (snd)
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(if (stringp snd) `(play-file ,snd)
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`(play ,snd)))
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(if (not (boundp '*sal-compiler-debug*))
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(setf *sal-compiler-debug* nil))
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(defmacro sal-simrep (variable iterations body)
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`(simrep (,variable ,iterations) ,body))
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(defmacro sal-seqrep (variable iterations body)
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`(seqrep (,variable ,iterations) ,body))
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;; function called in sal programs to exit the sal read-compile-run-print loop
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(defun sal-exit () (setf *sal-exit* t))
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;; read-eval-print loop for sal commands
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(defun sal ()
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(progv '(*breakenable* *tracenable* *sal-exit*)
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(list *sal-xlispbreak* *sal-xlispbreak* nil)
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(let (input line)
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|
(setf *sal-call-stack* nil)
|
|
(read-line) ; read the newline after the one the user
|
|
; typed to invoke this fn
|
|
(princ "Entering SAL mode ...\n");
|
|
(while (not *sal-exit*)
|
|
(princ "\nSAL> ")
|
|
(sal-trace-enter "SAL top-level command interpreter")
|
|
;; get input terminated by two returns
|
|
(setf input "")
|
|
(while (> (length (setf line (read-line))) 0)
|
|
(if *sal-secondary-prompt* (princ " ... "))
|
|
(setf input (strcat input "\n" line)))
|
|
;; input may have an extra return, remaining from previous read
|
|
;; if so, trim it because it affects line count in error messages
|
|
(if (and (> (length input) 0) (char= (char input 0) #\newline))
|
|
(setf input (subseq input 1)))
|
|
(sal-compile input t nil "<console>")
|
|
(sal-trace-exit))
|
|
(princ "Returning to Lisp ...\n")
|
|
t ; return value
|
|
)))
|
|
|
|
|
|
(defun sal-error-output (stack)
|
|
(if *sal-traceback* (sal-traceback))
|
|
(setf *sal-call-stack* stack)) ;; clear the stack
|
|
|
|
|
|
;; when true, top-level return statement is legal and compiled into MAIN
|
|
(setf *audacity-top-level-return-flag* nil)
|
|
|
|
;; SAL-COMPILE-AUDACITY -- special treatment of RETURN
|
|
;;
|
|
;; This works like SAL-COMPILE, but if there is a top-level
|
|
;; return statement (not normally legal), it is compiled into
|
|
;; a function named MAIN. This is a shorthand for Audacity plug-ins
|
|
;;
|
|
(defun sal-compile-audacity (input eval-flag multiple-statements filename)
|
|
(progv '(*audacity-top-level-return-flag*) '(t)
|
|
(sal-compile input eval-flag multiple-statements filename)))
|
|
|
|
|
|
;; SAL-COMPILE -- translate string or token list to lisp and eval
|
|
;;
|
|
;; input is either a string or a token list
|
|
;; eval-flag tells whether to evaluate the program or return the lisp
|
|
;; multiple-statements tells whether the input can contain multiple
|
|
;; top-level units (e.g. from a file) or just one (from command line)
|
|
;; returns:
|
|
;; if eval-flag, then nothing is returned
|
|
;; otherwise, returns nil if an error is encountered
|
|
;; otherwise, returns a list (PROGN p1 p2 p3 ...) where pn are lisp
|
|
;; expressions
|
|
;;
|
|
(defun sal-compile (input eval-flag multiple-statements filename)
|
|
;; save some globals because eval could call back recursively
|
|
(progv '(*sal-tokens* *sal-input* *sal-input-text*) '(nil nil nil)
|
|
(let (output remainder rslt stack)
|
|
(setf stack *sal-call-stack*)
|
|
;; if first input char is "(", then eval as a lisp expression:
|
|
;(display "sal-compile" input)(setf *sal-compiler-debug* t)
|
|
(cond ((input-starts-with-open-paren input)
|
|
;(print "input is lisp expression")
|
|
(errset
|
|
(print (eval (read (make-string-input-stream input)))) t))
|
|
(t ;; compile SAL expression(s):
|
|
(loop
|
|
(setf output (sal-parse nil nil input multiple-statements
|
|
filename))
|
|
(cond ((first output) ; successful parse
|
|
(setf remainder *sal-tokens*)
|
|
(setf output (second output))
|
|
(when *sal-compiler-debug*
|
|
(terpri)
|
|
(pprint output))
|
|
(cond (eval-flag ;; evaluate the compiled code
|
|
(cond ((null (errset (eval output) t))
|
|
(sal-error-output stack)
|
|
(return)))) ;; stop on error
|
|
(t
|
|
(push output rslt)))
|
|
;(display "sal-compile after eval"
|
|
; remainder *sal-tokens*)
|
|
;; if there are statements left over, maybe compile again
|
|
(cond ((and multiple-statements remainder)
|
|
;; move remainder to input and iterate
|
|
(setf input remainder))
|
|
;; see if we've compiled everything
|
|
((and (not eval-flag) (not remainder))
|
|
(return (cons 'progn (reverse rslt))))
|
|
;; if eval but no more input, return
|
|
((not remainder)
|
|
(return))))
|
|
(t ; error encountered
|
|
(return)))))))))
|
|
|
|
;; SAL just evaluates lisp expression if it starts with open-paren,
|
|
;; but sometimes reader reads previous newline(s), so here we
|
|
;; trim off initial newlines and check if first non-newline is open-paren
|
|
(defun input-starts-with-open-paren (input)
|
|
(let ((i 0))
|
|
(while (and (stringp input)
|
|
(> (length input) i)
|
|
(eq (char input i) #\newline))
|
|
(incf i))
|
|
(and (stringp input)
|
|
(> (length input) i)
|
|
(eq (char input i) #\())))
|