--- /dev/null
+;;;; "format.scm" Common LISP text output formatter for SLIB
+;;; Written 1992-1994 by Dirk Lutzebaeck (lutzeb@cs.tu-berlin.de)
+;;; Assimilated into Guile May 1999
+;;
+;; This code is in the public domain.
+
+;; Authors of the original version (< 1.4) were Ken Dickey and Aubrey Jaffer.
+;; Please send error reports to bug-guile@gnu.org.
+;; For documentation see slib.texi and format.doc.
+;; For testing load formatst.scm.
+;;
+;; Version 3.0
+
+(define-module (ice-9 format)
+ :use-module (ice-9 and-let-star)
+ :autoload (ice-9 pretty-print) (pretty-print)
+ :replace (format)
+ :export (format:symbol-case-conv
+ format:iobj-case-conv
+ format:expch))
+
+;;; Configuration ------------------------------------------------------------
+
+(define format:symbol-case-conv #f)
+;; Symbols are converted by symbol->string so the case of the printed
+;; symbols is implementation dependent. format:symbol-case-conv is a
+;; one arg closure which is either #f (no conversion), string-upcase!,
+;; string-downcase! or string-capitalize!.
+
+(define format:iobj-case-conv #f)
+;; As format:symbol-case-conv but applies for the representation of
+;; implementation internal objects.
+
+(define format:expch #\E)
+;; The character prefixing the exponent value in ~e printing.
+
+(define format:floats (provided? 'inexact))
+;; Detects if the scheme system implements flonums (see at eof).
+
+(define format:complex-numbers (provided? 'complex))
+;; Detects if the scheme system implements complex numbers.
+
+(define format:radix-pref (char=? #\# (string-ref (number->string 8 8) 0)))
+;; Detects if number->string adds a radix prefix.
+
+(define format:ascii-non-printable-charnames
+ '#("nul" "soh" "stx" "etx" "eot" "enq" "ack" "bel"
+ "bs" "ht" "nl" "vt" "np" "cr" "so" "si"
+ "dle" "dc1" "dc2" "dc3" "dc4" "nak" "syn" "etb"
+ "can" "em" "sub" "esc" "fs" "gs" "rs" "us" "space"))
+
+;;; End of configuration ----------------------------------------------------
+
+(define (format . args)
+ (letrec
+ ((format:version "3.0")
+ (format:port #f) ; curr. format output port
+ (format:output-col 0) ; curr. format output tty column
+ (format:flush-output #f) ; flush output at end of formatting
+ (format:case-conversion #f)
+ (format:args #f)
+ (format:pos 0) ; curr. format string parsing position
+ (format:arg-pos 0) ; curr. format argument position
+ ; this is global for error presentation
+
+ ;; format string and char output routines on format:port
+
+ (format:out-str
+ (lambda (str)
+ (if format:case-conversion
+ (display (format:case-conversion str) format:port)
+ (display str format:port))
+ (set! format:output-col
+ (+ format:output-col (string-length str)))))
+
+ (format:out-char
+ (lambda (ch)
+ (if format:case-conversion
+ (display (format:case-conversion (string ch))
+ format:port)
+ (write-char ch format:port))
+ (set! format:output-col
+ (if (char=? ch #\newline)
+ 0
+ (+ format:output-col 1)))))
+
+ ;;(define (format:out-substr str i n) ; this allocates a new string
+ ;; (display (substring str i n) format:port)
+ ;; (set! format:output-col (+ format:output-col n)))
+
+ (format:out-substr
+ (lambda (str i n)
+ (do ((k i (+ k 1)))
+ ((= k n))
+ (write-char (string-ref str k) format:port))
+ (set! format:output-col (+ format:output-col (- n i)))))
+
+ ;;(define (format:out-fill n ch) ; this allocates a new string
+ ;; (format:out-str (make-string n ch)))
+
+ (format:out-fill
+ (lambda (n ch)
+ (do ((i 0 (+ i 1)))
+ ((= i n))
+ (write-char ch format:port))
+ (set! format:output-col (+ format:output-col n))))
+
+ ;; format's user error handler
+
+ (format:error
+ (lambda args ; never returns!
+ (let ((format-args format:args)
+ (port (current-error-port)))
+ (set! format:error format:intern-error)
+ (if (and (>= (length format:args) 2)
+ (string? (cadr format:args)))
+ (let ((format-string (cadr format-args)))
+ (if (not (zero? format:arg-pos))
+ (set! format:arg-pos (- format:arg-pos 1)))
+ (format port
+ "~%FORMAT: error with call: (format ~a \"~a<===~a\" ~
+ ~{~a ~}===>~{~a ~})~% "
+ (car format:args)
+ (substring format-string 0 format:pos)
+ (substring format-string format:pos
+ (string-length format-string))
+ (list-head (cddr format:args) format:arg-pos)
+ (list-tail (cddr format:args) format:arg-pos)))
+ (format port
+ "~%FORMAT: error with call: (format~{ ~a~})~% "
+ format:args))
+ (apply format port args)
+ (newline port)
+ (set! format:error format:error-save)
+ (format:abort))))
+
+ (format:intern-error
+ (lambda args
+ ;;if something goes wrong in format:error
+ (display "FORMAT: INTERNAL ERROR IN FORMAT:ERROR!") (newline)
+ (display " format args: ") (write format:args) (newline)
+ (display " error args: ") (write args) (newline)
+ (set! format:error format:error-save)
+ (format:abort)))
+
+ (format:error-save #f)
+
+ (format:format
+ (lambda args ; the formatter entry
+ (set! format:args args)
+ (set! format:arg-pos 0)
+ (set! format:pos 0)
+ (if (< (length args) 1)
+ (format:error "not enough arguments"))
+
+ ;; If the first argument is a string, then that's the format string.
+ ;; (Scheme->C)
+ ;; In this case, put the argument list in canonical form.
+ (let ((args (if (string? (car args))
+ (cons #f args)
+ args)))
+ ;; Use this canonicalized version when reporting errors.
+ (set! format:args args)
+
+ (let ((destination (car args))
+ (arglist (cdr args)))
+ (cond
+ ((or (and (boolean? destination) ; port output
+ destination)
+ (output-port? destination)
+ (number? destination))
+ (format:out (cond
+ ((boolean? destination) (current-output-port))
+ ((output-port? destination) destination)
+ ((number? destination) (current-error-port)))
+ (car arglist) (cdr arglist)))
+ ((and (boolean? destination) ; string output
+ (not destination))
+ (call-with-output-string
+ (lambda (port) (format:out port (car arglist) (cdr arglist)))))
+ (else
+ (format:error "illegal destination `~a'" destination)))))))
+
+ (format:out ; the output handler for a port
+ (lambda (port fmt args)
+ (set! format:port port) ; global port for
+ ; output routines
+ (set! format:case-conversion #f) ; modifier case
+ ; conversion procedure
+ (set! format:flush-output #f) ; ~! reset
+ (and-let* ((col (port-column port))) ; get current column from port
+ (set! format:output-col col))
+ (let ((arg-pos (format:format-work fmt args))
+ (arg-len (length args)))
+ (cond
+ ((> arg-pos arg-len)
+ (set! format:arg-pos (+ arg-len 1))
+ (display format:arg-pos)
+ (format:error "~a missing argument~:p" (- arg-pos arg-len)))
+ (else
+ (if format:flush-output (force-output port))
+ #t)))))
+
+ (format:parameter-characters
+ '(#\0 #\1 #\2 #\3 #\4 #\5 #\6 #\7 #\8 #\9 #\- #\+ #\v #\# #\'))
+
+ (format:format-work ; does the formatting work
+ (lambda (format-string arglist)
+ (letrec
+ ((format-string-len (string-length format-string))
+ (arg-pos 0) ; argument position in arglist
+ (arg-len (length arglist)) ; number of arguments
+ (modifier #f) ; 'colon | 'at | 'colon-at | #f
+ (params '()) ; directive parameter list
+ (param-value-found #f) ; a directive
+ ; parameter value
+ ; found
+ (conditional-nest 0) ; conditional nesting level
+ (clause-pos 0) ; last cond. clause
+ ; beginning char pos
+ (clause-default #f) ; conditional default
+ ; clause string
+ (clauses '()) ; conditional clause
+ ; string list
+ (conditional-type #f) ; reflects the
+ ; contional modifiers
+ (conditional-arg #f) ; argument to apply the conditional
+ (iteration-nest 0) ; iteration nesting level
+ (iteration-pos 0) ; iteration string
+ ; beginning char pos
+ (iteration-type #f) ; reflects the
+ ; iteration modifiers
+ (max-iterations #f) ; maximum number of
+ ; iterations
+ (recursive-pos-save format:pos)
+
+ (next-char ; gets the next char
+ ; from format-string
+ (lambda ()
+ (let ((ch (peek-next-char)))
+ (set! format:pos (+ 1 format:pos))
+ ch)))
+
+ (peek-next-char
+ (lambda ()
+ (if (>= format:pos format-string-len)
+ (format:error "illegal format string")
+ (string-ref format-string format:pos))))
+
+ (one-positive-integer?
+ (lambda (params)
+ (cond
+ ((null? params) #f)
+ ((and (integer? (car params))
+ (>= (car params) 0)
+ (= (length params) 1)) #t)
+ (else
+ (format:error
+ "one positive integer parameter expected")))))
+
+ (next-arg
+ (lambda ()
+ (if (>= arg-pos arg-len)
+ (begin
+ (set! format:arg-pos (+ arg-len 1))
+ (format:error "missing argument(s)")))
+ (add-arg-pos 1)
+ (list-ref arglist (- arg-pos 1))))
+
+ (prev-arg
+ (lambda ()
+ (add-arg-pos -1)
+ (if (negative? arg-pos)
+ (format:error "missing backward argument(s)"))
+ (list-ref arglist arg-pos)))
+
+ (rest-args
+ (lambda ()
+ (let loop ((l arglist) (k arg-pos)) ; list-tail definition
+ (if (= k 0) l (loop (cdr l) (- k 1))))))
+
+ (add-arg-pos
+ (lambda (n)
+ (set! arg-pos (+ n arg-pos))
+ (set! format:arg-pos arg-pos)))
+
+ (anychar-dispatch ; dispatches the format-string
+ (lambda ()
+ (if (>= format:pos format-string-len)
+ arg-pos ; used for ~? continuance
+ (let ((char (next-char)))
+ (cond
+ ((char=? char #\~)
+ (set! modifier #f)
+ (set! params '())
+ (set! param-value-found #f)
+ (tilde-dispatch))
+ (else
+ (if (and (zero? conditional-nest)
+ (zero? iteration-nest))
+ (format:out-char char))
+ (anychar-dispatch)))))))
+
+ (tilde-dispatch
+ (lambda ()
+ (cond
+ ((>= format:pos format-string-len)
+ (format:out-str "~") ; tilde at end of
+ ; string is just
+ ; output
+ arg-pos) ; used for ~?
+ ; continuance
+ ((and (or (zero? conditional-nest)
+ (memv (peek-next-char) ; find conditional
+ ; directives
+ (append '(#\[ #\] #\; #\: #\@ #\^)
+ format:parameter-characters)))
+ (or (zero? iteration-nest)
+ (memv (peek-next-char) ; find iteration
+ ; directives
+ (append '(#\{ #\} #\: #\@ #\^)
+ format:parameter-characters))))
+ (case (char-upcase (next-char))
+
+ ;; format directives
+
+ ((#\A) ; Any -- for humans
+ (set! format:read-proof
+ (memq modifier '(colon colon-at)))
+ (format:out-obj-padded (memq modifier '(at colon-at))
+ (next-arg) #f params)
+ (anychar-dispatch))
+ ((#\S) ; Slashified -- for parsers
+ (set! format:read-proof
+ (memq modifier '(colon colon-at)))
+ (format:out-obj-padded (memq modifier '(at colon-at))
+ (next-arg) #t params)
+ (anychar-dispatch))
+ ((#\D) ; Decimal
+ (format:out-num-padded modifier (next-arg) params 10)
+ (anychar-dispatch))
+ ((#\X) ; Hexadecimal
+ (format:out-num-padded modifier (next-arg) params 16)
+ (anychar-dispatch))
+ ((#\O) ; Octal
+ (format:out-num-padded modifier (next-arg) params 8)
+ (anychar-dispatch))
+ ((#\B) ; Binary
+ (format:out-num-padded modifier (next-arg) params 2)
+ (anychar-dispatch))
+ ((#\R)
+ (if (null? params)
+ (format:out-obj-padded ; Roman, cardinal,
+ ; ordinal numerals
+ #f
+ ((case modifier
+ ((at) format:num->roman)
+ ((colon-at) format:num->old-roman)
+ ((colon) format:num->ordinal)
+ (else format:num->cardinal))
+ (next-arg))
+ #f params)
+ (format:out-num-padded ; any Radix
+ modifier (next-arg) (cdr params) (car params)))
+ (anychar-dispatch))
+ ((#\F) ; Fixed-format floating-point
+ (if format:floats
+ (format:out-fixed modifier (next-arg) params)
+ (format:out-str (number->string (next-arg))))
+ (anychar-dispatch))
+ ((#\E) ; Exponential floating-point
+ (if format:floats
+ (format:out-expon modifier (next-arg) params)
+ (format:out-str (number->string (next-arg))))
+ (anychar-dispatch))
+ ((#\G) ; General floating-point
+ (if format:floats
+ (format:out-general modifier (next-arg) params)
+ (format:out-str (number->string (next-arg))))
+ (anychar-dispatch))
+ ((#\$) ; Dollars floating-point
+ (if format:floats
+ (format:out-dollar modifier (next-arg) params)
+ (format:out-str (number->string (next-arg))))
+ (anychar-dispatch))
+ ((#\I) ; Complex numbers
+ (if (not format:complex-numbers)
+ (format:error
+ "complex numbers not supported by this scheme system"))
+ (let ((z (next-arg)))
+ (if (not (complex? z))
+ (format:error "argument not a complex number"))
+ (format:out-fixed modifier (real-part z) params)
+ (format:out-fixed 'at (imag-part z) params)
+ (format:out-char #\i))
+ (anychar-dispatch))
+ ((#\C) ; Character
+ (let ((ch (if (one-positive-integer? params)
+ (integer->char (car params))
+ (next-arg))))
+ (if (not (char? ch))
+ (format:error "~~c expects a character"))
+ (case modifier
+ ((at)
+ (format:out-str (format:char->str ch)))
+ ((colon)
+ (let ((c (char->integer ch)))
+ (if (< c 0)
+ (set! c (+ c 256))) ; compensate
+ ; complement
+ ; impl.
+ (cond
+ ((< c #x20) ; assumes that control
+ ; chars are < #x20
+ (format:out-char #\^)
+ (format:out-char
+ (integer->char (+ c #x40))))
+ ((>= c #x7f)
+ (format:out-str "#\\")
+ (format:out-str
+ (if format:radix-pref
+ (let ((s (number->string c 8)))
+ (substring s 2 (string-length s)))
+ (number->string c 8))))
+ (else
+ (format:out-char ch)))))
+ (else (format:out-char ch))))
+ (anychar-dispatch))
+ ((#\P) ; Plural
+ (if (memq modifier '(colon colon-at))
+ (prev-arg))
+ (let ((arg (next-arg)))
+ (if (not (number? arg))
+ (format:error "~~p expects a number argument"))
+ (if (= arg 1)
+ (if (memq modifier '(at colon-at))
+ (format:out-char #\y))
+ (if (memq modifier '(at colon-at))
+ (format:out-str "ies")
+ (format:out-char #\s))))
+ (anychar-dispatch))
+ ((#\~) ; Tilde
+ (if (one-positive-integer? params)
+ (format:out-fill (car params) #\~)
+ (format:out-char #\~))
+ (anychar-dispatch))
+ ((#\%) ; Newline
+ (if (one-positive-integer? params)
+ (format:out-fill (car params) #\newline)
+ (format:out-char #\newline))
+ (set! format:output-col 0)
+ (anychar-dispatch))
+ ((#\&) ; Fresh line
+ (if (one-positive-integer? params)
+ (begin
+ (if (> (car params) 0)
+ (format:out-fill (- (car params)
+ (if (>
+ format:output-col
+ 0) 0 1))
+ #\newline))
+ (set! format:output-col 0))
+ (if (> format:output-col 0)
+ (format:out-char #\newline)))
+ (anychar-dispatch))
+ ((#\_) ; Space character
+ (if (one-positive-integer? params)
+ (format:out-fill (car params) #\space)
+ (format:out-char #\space))
+ (anychar-dispatch))
+ ((#\/) ; Tabulator character
+ (if (one-positive-integer? params)
+ (format:out-fill (car params) #\tab)
+ (format:out-char #\tab))
+ (anychar-dispatch))
+ ((#\|) ; Page seperator
+ (if (one-positive-integer? params)
+ (format:out-fill (car params) #\page)
+ (format:out-char #\page))
+ (set! format:output-col 0)
+ (anychar-dispatch))
+ ((#\T) ; Tabulate
+ (format:tabulate modifier params)
+ (anychar-dispatch))
+ ((#\Y) ; Pretty-print
+ (pretty-print (next-arg) format:port)
+ (set! format:output-col 0)
+ (anychar-dispatch))
+ ((#\? #\K) ; Indirection (is "~K" in T-Scheme)
+ (cond
+ ((memq modifier '(colon colon-at))
+ (format:error "illegal modifier in ~~?"))
+ ((eq? modifier 'at)
+ (let* ((frmt (next-arg))
+ (args (rest-args)))
+ (add-arg-pos (format:format-work frmt args))))
+ (else
+ (let* ((frmt (next-arg))
+ (args (next-arg)))
+ (format:format-work frmt args))))
+ (anychar-dispatch))
+ ((#\!) ; Flush output
+ (set! format:flush-output #t)
+ (anychar-dispatch))
+ ((#\newline) ; Continuation lines
+ (if (eq? modifier 'at)
+ (format:out-char #\newline))
+ (if (< format:pos format-string-len)
+ (do ((ch (peek-next-char) (peek-next-char)))
+ ((or (not (char-whitespace? ch))
+ (= format:pos (- format-string-len 1))))
+ (if (eq? modifier 'colon)
+ (format:out-char (next-char))
+ (next-char))))
+ (anychar-dispatch))
+ ((#\*) ; Argument jumping
+ (case modifier
+ ((colon) ; jump backwards
+ (if (one-positive-integer? params)
+ (do ((i 0 (+ i 1)))
+ ((= i (car params)))
+ (prev-arg))
+ (prev-arg)))
+ ((at) ; jump absolute
+ (set! arg-pos (if (one-positive-integer? params)
+ (car params) 0)))
+ ((colon-at)
+ (format:error "illegal modifier `:@' in ~~* directive"))
+ (else ; jump forward
+ (if (one-positive-integer? params)
+ (do ((i 0 (+ i 1)))
+ ((= i (car params)))
+ (next-arg))
+ (next-arg))))
+ (anychar-dispatch))
+ ((#\() ; Case conversion begin
+ (set! format:case-conversion
+ (case modifier
+ ((at) string-capitalize-first)
+ ((colon) string-capitalize)
+ ((colon-at) string-upcase)
+ (else string-downcase)))
+ (anychar-dispatch))
+ ((#\)) ; Case conversion end
+ (if (not format:case-conversion)
+ (format:error "missing ~~("))
+ (set! format:case-conversion #f)
+ (anychar-dispatch))
+ ((#\[) ; Conditional begin
+ (set! conditional-nest (+ conditional-nest 1))
+ (cond
+ ((= conditional-nest 1)
+ (set! clause-pos format:pos)
+ (set! clause-default #f)
+ (set! clauses '())
+ (set! conditional-type
+ (case modifier
+ ((at) 'if-then)
+ ((colon) 'if-else-then)
+ ((colon-at) (format:error "illegal modifier in ~~["))
+ (else 'num-case)))
+ (set! conditional-arg
+ (if (one-positive-integer? params)
+ (car params)
+ (next-arg)))))
+ (anychar-dispatch))
+ ((#\;) ; Conditional separator
+ (if (zero? conditional-nest)
+ (format:error "~~; not in ~~[~~] conditional"))
+ (if (not (null? params))
+ (format:error "no parameter allowed in ~~;"))
+ (if (= conditional-nest 1)
+ (let ((clause-str
+ (cond
+ ((eq? modifier 'colon)
+ (set! clause-default #t)
+ (substring format-string clause-pos
+ (- format:pos 3)))
+ ((memq modifier '(at colon-at))
+ (format:error "illegal modifier in ~~;"))
+ (else
+ (substring format-string clause-pos
+ (- format:pos 2))))))
+ (set! clauses (append clauses (list clause-str)))
+ (set! clause-pos format:pos)))
+ (anychar-dispatch))
+ ((#\]) ; Conditional end
+ (if (zero? conditional-nest) (format:error "missing ~~["))
+ (set! conditional-nest (- conditional-nest 1))
+ (if modifier
+ (format:error "no modifier allowed in ~~]"))
+ (if (not (null? params))
+ (format:error "no parameter allowed in ~~]"))
+ (cond
+ ((zero? conditional-nest)
+ (let ((clause-str (substring format-string clause-pos
+ (- format:pos 2))))
+ (if clause-default
+ (set! clause-default clause-str)
+ (set! clauses (append clauses (list clause-str)))))
+ (case conditional-type
+ ((if-then)
+ (if conditional-arg
+ (format:format-work (car clauses)
+ (list conditional-arg))))
+ ((if-else-then)
+ (add-arg-pos
+ (format:format-work (if conditional-arg
+ (cadr clauses)
+ (car clauses))
+ (rest-args))))
+ ((num-case)
+ (if (or (not (integer? conditional-arg))
+ (< conditional-arg 0))
+ (format:error "argument not a positive integer"))
+ (if (not (and (>= conditional-arg (length clauses))
+ (not clause-default)))
+ (add-arg-pos
+ (format:format-work
+ (if (>= conditional-arg (length clauses))
+ clause-default
+ (list-ref clauses conditional-arg))
+ (rest-args))))))))
+ (anychar-dispatch))
+ ((#\{) ; Iteration begin
+ (set! iteration-nest (+ iteration-nest 1))
+ (cond
+ ((= iteration-nest 1)
+ (set! iteration-pos format:pos)
+ (set! iteration-type
+ (case modifier
+ ((at) 'rest-args)
+ ((colon) 'sublists)
+ ((colon-at) 'rest-sublists)
+ (else 'list)))
+ (set! max-iterations (if (one-positive-integer? params)
+ (car params) #f))))
+ (anychar-dispatch))
+ ((#\}) ; Iteration end
+ (if (zero? iteration-nest) (format:error "missing ~~{"))
+ (set! iteration-nest (- iteration-nest 1))
+ (case modifier
+ ((colon)
+ (if (not max-iterations) (set! max-iterations 1)))
+ ((colon-at at) (format:error "illegal modifier")))
+ (if (not (null? params))
+ (format:error "no parameters allowed in ~~}"))
+ (if (zero? iteration-nest)
+ (let ((iteration-str
+ (substring format-string iteration-pos
+ (- format:pos (if modifier 3 2)))))
+ (if (string=? iteration-str "")
+ (set! iteration-str (next-arg)))
+ (case iteration-type
+ ((list)
+ (let ((args (next-arg))
+ (args-len 0))
+ (if (not (list? args))
+ (format:error "expected a list argument"))
+ (set! args-len (length args))
+ (do ((arg-pos 0 (+ arg-pos
+ (format:format-work
+ iteration-str
+ (list-tail args arg-pos))))
+ (i 0 (+ i 1)))
+ ((or (>= arg-pos args-len)
+ (and max-iterations
+ (>= i max-iterations)))))))
+ ((sublists)
+ (let ((args (next-arg))
+ (args-len 0))
+ (if (not (list? args))
+ (format:error "expected a list argument"))
+ (set! args-len (length args))
+ (do ((arg-pos 0 (+ arg-pos 1)))
+ ((or (>= arg-pos args-len)
+ (and max-iterations
+ (>= arg-pos max-iterations))))
+ (let ((sublist (list-ref args arg-pos)))
+ (if (not (list? sublist))
+ (format:error
+ "expected a list of lists argument"))
+ (format:format-work iteration-str sublist)))))
+ ((rest-args)
+ (let* ((args (rest-args))
+ (args-len (length args))
+ (usedup-args
+ (do ((arg-pos 0 (+ arg-pos
+ (format:format-work
+ iteration-str
+ (list-tail
+ args arg-pos))))
+ (i 0 (+ i 1)))
+ ((or (>= arg-pos args-len)
+ (and max-iterations
+ (>= i max-iterations)))
+ arg-pos))))
+ (add-arg-pos usedup-args)))
+ ((rest-sublists)
+ (let* ((args (rest-args))
+ (args-len (length args))
+ (usedup-args
+ (do ((arg-pos 0 (+ arg-pos 1)))
+ ((or (>= arg-pos args-len)
+ (and max-iterations
+ (>= arg-pos max-iterations)))
+ arg-pos)
+ (let ((sublist (list-ref args arg-pos)))
+ (if (not (list? sublist))
+ (format:error "expected list arguments"))
+ (format:format-work iteration-str sublist)))))
+ (add-arg-pos usedup-args)))
+ (else (format:error "internal error in ~~}")))))
+ (anychar-dispatch))
+ ((#\^) ; Up and out
+ (let* ((continue
+ (cond
+ ((not (null? params))
+ (not
+ (case (length params)
+ ((1) (zero? (car params)))
+ ((2) (= (list-ref params 0) (list-ref params 1)))
+ ((3) (<= (list-ref params 0)
+ (list-ref params 1)
+ (list-ref params 2)))
+ (else (format:error "too much parameters")))))
+ (format:case-conversion ; if conversion stop conversion
+ (set! format:case-conversion string-copy) #t)
+ ((= iteration-nest 1) #t)
+ ((= conditional-nest 1) #t)
+ ((>= arg-pos arg-len)
+ (set! format:pos format-string-len) #f)
+ (else #t))))
+ (if continue
+ (anychar-dispatch))))
+
+ ;; format directive modifiers and parameters
+
+ ((#\@) ; `@' modifier
+ (if (memq modifier '(at colon-at))
+ (format:error "double `@' modifier"))
+ (set! modifier (if (eq? modifier 'colon) 'colon-at 'at))
+ (tilde-dispatch))
+ ((#\:) ; `:' modifier
+ (if (memq modifier '(colon colon-at))
+ (format:error "double `:' modifier"))
+ (set! modifier (if (eq? modifier 'at) 'colon-at 'colon))
+ (tilde-dispatch))
+ ((#\') ; Character parameter
+ (if modifier (format:error "misplaced modifier"))
+ (set! params (append params (list (char->integer (next-char)))))
+ (set! param-value-found #t)
+ (tilde-dispatch))
+ ((#\0 #\1 #\2 #\3 #\4 #\5 #\6 #\7 #\8 #\9 #\- #\+) ; num. paramtr
+ (if modifier (format:error "misplaced modifier"))
+ (let ((num-str-beg (- format:pos 1))
+ (num-str-end format:pos))
+ (do ((ch (peek-next-char) (peek-next-char)))
+ ((not (char-numeric? ch)))
+ (next-char)
+ (set! num-str-end (+ 1 num-str-end)))
+ (set! params
+ (append params
+ (list (string->number
+ (substring format-string
+ num-str-beg
+ num-str-end))))))
+ (set! param-value-found #t)
+ (tilde-dispatch))
+ ((#\V) ; Variable parameter from next argum.
+ (if modifier (format:error "misplaced modifier"))
+ (set! params (append params (list (next-arg))))
+ (set! param-value-found #t)
+ (tilde-dispatch))
+ ((#\#) ; Parameter is number of remaining args
+ (if param-value-found (format:error "misplaced '#'"))
+ (if modifier (format:error "misplaced modifier"))
+ (set! params (append params (list (length (rest-args)))))
+ (set! param-value-found #t)
+ (tilde-dispatch))
+ ((#\,) ; Parameter separators
+ (if modifier (format:error "misplaced modifier"))
+ (if (not param-value-found)
+ (set! params (append params '(#f)))) ; append empty paramtr
+ (set! param-value-found #f)
+ (tilde-dispatch))
+ ((#\Q) ; Inquiry messages
+ (if (eq? modifier 'colon)
+ (format:out-str format:version)
+ (let ((nl (string #\newline)))
+ (format:out-str
+ (string-append
+ "SLIB Common LISP format version " format:version nl
+ " (C) copyright 1992-1994 by Dirk Lutzebaeck" nl
+ " please send bug reports to `lutzeb@cs.tu-berlin.de'"
+ nl))))
+ (anychar-dispatch))
+ (else ; Unknown tilde directive
+ (format:error "unknown control character `~c'"
+ (string-ref format-string (- format:pos 1))))))
+ (else (anychar-dispatch)))))) ; in case of conditional
+
+ (set! format:pos 0)
+ (set! format:arg-pos 0)
+ (anychar-dispatch) ; start the formatting
+ (set! format:pos recursive-pos-save)
+ arg-pos))) ; return the position in the arg. list
+
+ ;; when format:read-proof is true, format:obj->str will wrap
+ ;; result strings starting with "#<" in an extra pair of double
+ ;; quotes.
+
+ (format:read-proof #f)
+
+ ;; format:obj->str returns a R4RS representation as a string of
+ ;; an arbitrary scheme object.
+
+ (format:obj->str
+ (lambda (obj slashify)
+ (let ((res (if slashify
+ (object->string obj)
+ (with-output-to-string (lambda () (display obj))))))
+ (if (and format:read-proof (string-prefix? "#<" res))
+ (object->string res)
+ res))))
+
+ ;; format:char->str converts a character into a slashified string as
+ ;; done by `write'. The procedure is dependent on the integer
+ ;; representation of characters and assumes a character number according to
+ ;; the ASCII character set.
+
+ (format:char->str
+ (lambda (ch)
+ (let ((int-rep (char->integer ch)))
+ (if (< int-rep 0) ; if chars are [-128...+127]
+ (set! int-rep (+ int-rep 256)))
+ (string-append
+ "#\\"
+ (cond
+ ((char=? ch #\newline) "newline")
+ ((and (>= int-rep 0) (<= int-rep 32))
+ (vector-ref format:ascii-non-printable-charnames int-rep))
+ ((= int-rep 127) "del")
+ ((>= int-rep 128) ; octal representation
+ (if format:radix-pref
+ (let ((s (number->string int-rep 8)))
+ (substring s 2 (string-length s)))
+ (number->string int-rep 8)))
+ (else (string ch)))))))
+
+ (format:space-ch (char->integer #\space))
+ (format:zero-ch (char->integer #\0))
+
+ (format:par
+ (lambda (pars length index default name)
+ (if (> length index)
+ (let ((par (list-ref pars index)))
+ (if par
+ (if name
+ (if (< par 0)
+ (format:error
+ "~s parameter must be a positive integer" name)
+ par)
+ par)
+ default))
+ default)))
+
+ (format:out-obj-padded
+ (lambda (pad-left obj slashify pars)
+ (if (null? pars)
+ (format:out-str (format:obj->str obj slashify))
+ (let ((l (length pars)))
+ (let ((mincol (format:par pars l 0 0 "mincol"))
+ (colinc (format:par pars l 1 1 "colinc"))
+ (minpad (format:par pars l 2 0 "minpad"))
+ (padchar (integer->char
+ (format:par pars l 3 format:space-ch #f)))
+ (objstr (format:obj->str obj slashify)))
+ (if (not pad-left)
+ (format:out-str objstr))
+ (do ((objstr-len (string-length objstr))
+ (i minpad (+ i colinc)))
+ ((>= (+ objstr-len i) mincol)
+ (format:out-fill i padchar)))
+ (if pad-left
+ (format:out-str objstr)))))))
+
+ (format:out-num-padded
+ (lambda (modifier number pars radix)
+ (if (not (integer? number)) (format:error "argument not an integer"))
+ (let ((numstr (number->string number radix)))
+ (if (and format:radix-pref (not (= radix 10)))
+ (set! numstr (substring numstr 2 (string-length numstr))))
+ (if (and (null? pars) (not modifier))
+ (format:out-str numstr)
+ (let ((l (length pars))
+ (numstr-len (string-length numstr)))
+ (let ((mincol (format:par pars l 0 #f "mincol"))
+ (padchar (integer->char
+ (format:par pars l 1 format:space-ch #f)))
+ (commachar (integer->char
+ (format:par pars l 2 (char->integer #\,) #f)))
+ (commawidth (format:par pars l 3 3 "commawidth")))
+ (if mincol
+ (let ((numlen numstr-len)) ; calc. the output len of number
+ (if (and (memq modifier '(at colon-at)) (>= number 0))
+ (set! numlen (+ numlen 1)))
+ (if (memq modifier '(colon colon-at))
+ (set! numlen (+ (quotient (- numstr-len
+ (if (< number 0) 2 1))
+ commawidth)
+ numlen)))
+ (if (> mincol numlen)
+ (format:out-fill (- mincol numlen) padchar))))
+ (if (and (memq modifier '(at colon-at))
+ (>= number 0))
+ (format:out-char #\+))
+ (if (memq modifier '(colon colon-at)) ; insert comma character
+ (let ((start (remainder numstr-len commawidth))
+ (ns (if (< number 0) 1 0)))
+ (format:out-substr numstr 0 start)
+ (do ((i start (+ i commawidth)))
+ ((>= i numstr-len))
+ (if (> i ns)
+ (format:out-char commachar))
+ (format:out-substr numstr i (+ i commawidth))))
+ (format:out-str numstr))))))))
+
+ (format:tabulate
+ (lambda (modifier pars)
+ (let ((l (length pars)))
+ (let ((colnum (format:par pars l 0 1 "colnum"))
+ (colinc (format:par pars l 1 1 "colinc"))
+ (padch (integer->char (format:par pars l 2 format:space-ch #f))))
+ (case modifier
+ ((colon colon-at)
+ (format:error "unsupported modifier for ~~t"))
+ ((at) ; relative tabulation
+ (format:out-fill
+ (if (= colinc 0)
+ colnum ; colnum = colrel
+ (do ((c 0 (+ c colinc))
+ (col (+ format:output-col colnum)))
+ ((>= c col)
+ (- c format:output-col))))
+ padch))
+ (else ; absolute tabulation
+ (format:out-fill
+ (cond
+ ((< format:output-col colnum)
+ (- colnum format:output-col))
+ ((= colinc 0)
+ 0)
+ (else
+ (do ((c colnum (+ c colinc)))
+ ((>= c format:output-col)
+ (- c format:output-col)))))
+ padch)))))))
+
+
+ ;; roman numerals (from dorai@cs.rice.edu).
+
+ (format:roman-alist
+ '((1000 #\M) (500 #\D) (100 #\C) (50 #\L)
+ (10 #\X) (5 #\V) (1 #\I)))
+
+ (format:roman-boundary-values
+ '(100 100 10 10 1 1 #f))
+
+ (format:num->old-roman
+ (lambda (n)
+ (if (and (integer? n) (>= n 1))
+ (let loop ((n n)
+ (romans format:roman-alist)
+ (s '()))
+ (if (null? romans) (list->string (reverse s))
+ (let ((roman-val (caar romans))
+ (roman-dgt (cadar romans)))
+ (do ((q (quotient n roman-val) (- q 1))
+ (s s (cons roman-dgt s)))
+ ((= q 0)
+ (loop (remainder n roman-val)
+ (cdr romans) s))))))
+ (format:error "only positive integers can be romanized"))))
+
+ (format:num->roman
+ (lambda (n)
+ (if (and (integer? n) (> n 0))
+ (let loop ((n n)
+ (romans format:roman-alist)
+ (boundaries format:roman-boundary-values)
+ (s '()))
+ (if (null? romans)
+ (list->string (reverse s))
+ (let ((roman-val (caar romans))
+ (roman-dgt (cadar romans))
+ (bdry (car boundaries)))
+ (let loop2 ((q (quotient n roman-val))
+ (r (remainder n roman-val))
+ (s s))
+ (if (= q 0)
+ (if (and bdry (>= r (- roman-val bdry)))
+ (loop (remainder r bdry) (cdr romans)
+ (cdr boundaries)
+ (cons roman-dgt
+ (append
+ (cdr (assv bdry romans))
+ s)))
+ (loop r (cdr romans) (cdr boundaries) s))
+ (loop2 (- q 1) r (cons roman-dgt s)))))))
+ (format:error "only positive integers can be romanized"))))
+
+ ;; cardinals & ordinals (from dorai@cs.rice.edu)
+
+ (format:cardinal-ones-list
+ '(#f "one" "two" "three" "four" "five"
+ "six" "seven" "eight" "nine" "ten" "eleven" "twelve" "thirteen"
+ "fourteen" "fifteen" "sixteen" "seventeen" "eighteen"
+ "nineteen"))
+
+ (format:cardinal-tens-list
+ '(#f #f "twenty" "thirty" "forty" "fifty" "sixty" "seventy" "eighty"
+ "ninety"))
+
+ (format:num->cardinal999
+ (lambda (n)
+ ;this procedure is inspired by the Bruno Haible's CLisp
+ ;function format-small-cardinal, which converts numbers
+ ;in the range 1 to 999, and is used for converting each
+ ;thousand-block in a larger number
+ (let* ((hundreds (quotient n 100))
+ (tens+ones (remainder n 100))
+ (tens (quotient tens+ones 10))
+ (ones (remainder tens+ones 10)))
+ (append
+ (if (> hundreds 0)
+ (append
+ (string->list
+ (list-ref format:cardinal-ones-list hundreds))
+ (string->list" hundred")
+ (if (> tens+ones 0) '(#\space) '()))
+ '())
+ (if (< tens+ones 20)
+ (if (> tens+ones 0)
+ (string->list
+ (list-ref format:cardinal-ones-list tens+ones))
+ '())
+ (append
+ (string->list
+ (list-ref format:cardinal-tens-list tens))
+ (if (> ones 0)
+ (cons #\-
+ (string->list
+ (list-ref format:cardinal-ones-list ones)))
+ '())))))))
+
+ (format:cardinal-thousand-block-list
+ '("" " thousand" " million" " billion" " trillion" " quadrillion"
+ " quintillion" " sextillion" " septillion" " octillion" " nonillion"
+ " decillion" " undecillion" " duodecillion" " tredecillion"
+ " quattuordecillion" " quindecillion" " sexdecillion" " septendecillion"
+ " octodecillion" " novemdecillion" " vigintillion"))
+
+ (format:num->cardinal
+ (lambda (n)
+ (cond ((not (integer? n))
+ (format:error
+ "only integers can be converted to English cardinals"))
+ ((= n 0) "zero")
+ ((< n 0) (string-append "minus " (format:num->cardinal (- n))))
+ (else
+ (let ((power3-word-limit
+ (length format:cardinal-thousand-block-list)))
+ (let loop ((n n)
+ (power3 0)
+ (s '()))
+ (if (= n 0)
+ (list->string s)
+ (let ((n-before-block (quotient n 1000))
+ (n-after-block (remainder n 1000)))
+ (loop n-before-block
+ (+ power3 1)
+ (if (> n-after-block 0)
+ (append
+ (if (> n-before-block 0)
+ (string->list ", ") '())
+ (format:num->cardinal999 n-after-block)
+ (if (< power3 power3-word-limit)
+ (string->list
+ (list-ref
+ format:cardinal-thousand-block-list
+ power3))
+ (append
+ (string->list " times ten to the ")
+ (string->list
+ (format:num->ordinal
+ (* power3 3)))
+ (string->list " power")))
+ s)
+ s))))))))))
+
+ (format:ordinal-ones-list
+ '(#f "first" "second" "third" "fourth" "fifth"
+ "sixth" "seventh" "eighth" "ninth" "tenth" "eleventh" "twelfth"
+ "thirteenth" "fourteenth" "fifteenth" "sixteenth" "seventeenth"
+ "eighteenth" "nineteenth"))
+
+ (format:ordinal-tens-list
+ '(#f #f "twentieth" "thirtieth" "fortieth" "fiftieth" "sixtieth"
+ "seventieth" "eightieth" "ninetieth"))
+
+ (format:num->ordinal
+ (lambda (n)
+ (cond ((not (integer? n))
+ (format:error
+ "only integers can be converted to English ordinals"))
+ ((= n 0) "zeroth")
+ ((< n 0) (string-append "minus " (format:num->ordinal (- n))))
+ (else
+ (let ((hundreds (quotient n 100))
+ (tens+ones (remainder n 100)))
+ (string-append
+ (if (> hundreds 0)
+ (string-append
+ (format:num->cardinal (* hundreds 100))
+ (if (= tens+ones 0) "th" " "))
+ "")
+ (if (= tens+ones 0) ""
+ (if (< tens+ones 20)
+ (list-ref format:ordinal-ones-list tens+ones)
+ (let ((tens (quotient tens+ones 10))
+ (ones (remainder tens+ones 10)))
+ (if (= ones 0)
+ (list-ref format:ordinal-tens-list tens)
+ (string-append
+ (list-ref format:cardinal-tens-list tens)
+ "-"
+ (list-ref format:ordinal-ones-list ones))))
+ ))))))))
+
+ ;; format inf and nan.
+
+ (format:out-inf-nan
+ (lambda (number width digits edigits overch padch)
+ ;; inf and nan are always printed exactly as "+inf.0", "-inf.0" or
+ ;; "+nan.0", suitably justified in their field. We insist on
+ ;; printing this exact form so that the numbers can be read back in.
+
+ (let* ((str (number->string number))
+ (len (string-length str))
+ (dot (string-index str #\.))
+ (digits (+ (or digits 0)
+ (if edigits (+ edigits 2) 0))))
+ (if (and width overch (< width len))
+ (format:out-fill width (integer->char overch))
+ (let* ((leftpad (if width
+ (max (- width (max len (+ dot 1 digits))) 0)
+ 0))
+ (rightpad (if width
+ (max (- width leftpad len) 0)
+ 0))
+ (padch (integer->char (or padch format:space-ch))))
+ (format:out-fill leftpad padch)
+ (format:out-str str)
+ (format:out-fill rightpad padch))))))
+
+ ;; format fixed flonums (~F)
+
+ (format:out-fixed
+ (lambda (modifier number pars)
+ (if (not (or (number? number) (string? number)))
+ (format:error "argument is not a number or a number string"))
+
+ (let ((l (length pars)))
+ (let ((width (format:par pars l 0 #f "width"))
+ (digits (format:par pars l 1 #f "digits"))
+ (scale (format:par pars l 2 0 #f))
+ (overch (format:par pars l 3 #f #f))
+ (padch (format:par pars l 4 format:space-ch #f)))
+
+ (cond
+ ((or (inf? number) (nan? number))
+ (format:out-inf-nan number width digits #f overch padch))
+
+ (digits
+ (format:parse-float
+ (if (string? number) number (number->string number)) #t scale)
+ (if (<= (- format:fn-len format:fn-dot) digits)
+ (format:fn-zfill #f (- digits (- format:fn-len format:fn-dot)))
+ (format:fn-round digits))
+ (if width
+ (let ((numlen (+ format:fn-len 1)))
+ (if (or (not format:fn-pos?) (eq? modifier 'at))
+ (set! numlen (+ numlen 1)))
+ (if (and (= format:fn-dot 0) (> width (+ digits 1)))
+ (set! numlen (+ numlen 1)))
+ (if (< numlen width)
+ (format:out-fill (- width numlen) (integer->char padch)))
+ (if (and overch (> numlen width))
+ (format:out-fill width (integer->char overch))
+ (format:fn-out modifier (> width (+ digits 1)))))
+ (format:fn-out modifier #t)))
+
+ (else
+ (format:parse-float
+ (if (string? number) number (number->string number)) #t scale)
+ (format:fn-strip)
+ (if width
+ (let ((numlen (+ format:fn-len 1)))
+ (if (or (not format:fn-pos?) (eq? modifier 'at))
+ (set! numlen (+ numlen 1)))
+ (if (= format:fn-dot 0)
+ (set! numlen (+ numlen 1)))
+ (if (< numlen width)
+ (format:out-fill (- width numlen) (integer->char padch)))
+ (if (> numlen width) ; adjust precision if possible
+ (let ((dot-index (- numlen
+ (- format:fn-len format:fn-dot))))
+ (if (> dot-index width)
+ (if overch ; numstr too big for required width
+ (format:out-fill width (integer->char overch))
+ (format:fn-out modifier #t))
+ (begin
+ (format:fn-round (- width dot-index))
+ (format:fn-out modifier #t))))
+ (format:fn-out modifier #t)))
+ (format:fn-out modifier #t))))))))
+
+ ;; format exponential flonums (~E)
+
+ (format:out-expon
+ (lambda (modifier number pars)
+ (if (not (or (number? number) (string? number)))
+ (format:error "argument is not a number"))
+
+ (let ((l (length pars)))
+ (let ((width (format:par pars l 0 #f "width"))
+ (digits (format:par pars l 1 #f "digits"))
+ (edigits (format:par pars l 2 #f "exponent digits"))
+ (scale (format:par pars l 3 1 #f))
+ (overch (format:par pars l 4 #f #f))
+ (padch (format:par pars l 5 format:space-ch #f))
+ (expch (format:par pars l 6 #f #f)))
+
+ (cond
+ ((or (inf? number) (nan? number))
+ (format:out-inf-nan number width digits edigits overch padch))
+
+ (digits ; fixed precision
+
+ (let ((digits (if (> scale 0)
+ (if (< scale (+ digits 2))
+ (+ (- digits scale) 1)
+ 0)
+ digits)))
+ (format:parse-float
+ (if (string? number) number (number->string number)) #f scale)
+ (if (<= (- format:fn-len format:fn-dot) digits)
+ (format:fn-zfill #f (- digits (- format:fn-len format:fn-dot)))
+ (format:fn-round digits))
+ (if width
+ (if (and edigits overch (> format:en-len edigits))
+ (format:out-fill width (integer->char overch))
+ (let ((numlen (+ format:fn-len 3))) ; .E+
+ (if (or (not format:fn-pos?) (eq? modifier 'at))
+ (set! numlen (+ numlen 1)))
+ (if (and (= format:fn-dot 0) (> width (+ digits 1)))
+ (set! numlen (+ numlen 1)))
+ (set! numlen
+ (+ numlen
+ (if (and edigits (>= edigits format:en-len))
+ edigits
+ format:en-len)))
+ (if (< numlen width)
+ (format:out-fill (- width numlen)
+ (integer->char padch)))
+ (if (and overch (> numlen width))
+ (format:out-fill width (integer->char overch))
+ (begin
+ (format:fn-out modifier (> width (- numlen 1)))
+ (format:en-out edigits expch)))))
+ (begin
+ (format:fn-out modifier #t)
+ (format:en-out edigits expch)))))
+
+ (else
+ (format:parse-float
+ (if (string? number) number (number->string number)) #f scale)
+ (format:fn-strip)
+ (if width
+ (if (and edigits overch (> format:en-len edigits))
+ (format:out-fill width (integer->char overch))
+ (let ((numlen (+ format:fn-len 3))) ; .E+
+ (if (or (not format:fn-pos?) (eq? modifier 'at))
+ (set! numlen (+ numlen 1)))
+ (if (= format:fn-dot 0)
+ (set! numlen (+ numlen 1)))
+ (set! numlen
+ (+ numlen
+ (if (and edigits (>= edigits format:en-len))
+ edigits
+ format:en-len)))
+ (if (< numlen width)
+ (format:out-fill (- width numlen)
+ (integer->char padch)))
+ (if (> numlen width) ; adjust precision if possible
+ (let ((f (- format:fn-len format:fn-dot))) ; fract len
+ (if (> (- numlen f) width)
+ (if overch ; numstr too big for required width
+ (format:out-fill width
+ (integer->char overch))
+ (begin
+ (format:fn-out modifier #t)
+ (format:en-out edigits expch)))
+ (begin
+ (format:fn-round (+ (- f numlen) width))
+ (format:fn-out modifier #t)
+ (format:en-out edigits expch))))
+ (begin
+ (format:fn-out modifier #t)
+ (format:en-out edigits expch)))))
+ (begin
+ (format:fn-out modifier #t)
+ (format:en-out edigits expch)))))))))
+
+ ;; format general flonums (~G)
+
+ (format:out-general
+ (lambda (modifier number pars)
+ (if (not (or (number? number) (string? number)))
+ (format:error "argument is not a number or a number string"))
+
+ (let ((l (length pars)))
+ (let ((width (if (> l 0) (list-ref pars 0) #f))
+ (digits (if (> l 1) (list-ref pars 1) #f))
+ (edigits (if (> l 2) (list-ref pars 2) #f))
+ (overch (if (> l 4) (list-ref pars 4) #f))
+ (padch (if (> l 5) (list-ref pars 5) #f)))
+ (cond
+ ((or (inf? number) (nan? number))
+ ;; FIXME: this isn't right.
+ (format:out-inf-nan number width digits edigits overch padch))
+ (else
+ (format:parse-float
+ (if (string? number) number (number->string number)) #t 0)
+ (format:fn-strip)
+ (let* ((ee (if edigits (+ edigits 2) 4)) ; for the following algorithm
+ (ww (if width (- width ee) #f)) ; see Steele's CL book p.395
+ (n (if (= format:fn-dot 0) ; number less than (abs 1.0) ?
+ (- (format:fn-zlead))
+ format:fn-dot))
+ (d (if digits
+ digits
+ (max format:fn-len (min n 7)))) ; q = format:fn-len
+ (dd (- d n)))
+ (if (<= 0 dd d)
+ (begin
+ (format:out-fixed modifier number (list ww dd #f overch padch))
+ (format:out-fill ee #\space)) ;~@T not implemented yet
+ (format:out-expon modifier number pars)))))))))
+
+ ;; format dollar flonums (~$)
+
+ (format:out-dollar
+ (lambda (modifier number pars)
+ (if (not (or (number? number) (string? number)))
+ (format:error "argument is not a number or a number string"))
+
+ (let ((l (length pars)))
+ (let ((digits (format:par pars l 0 2 "digits"))
+ (mindig (format:par pars l 1 1 "mindig"))
+ (width (format:par pars l 2 0 "width"))
+ (padch (format:par pars l 3 format:space-ch #f)))
+
+ (cond
+ ((or (inf? number) (nan? number))
+ (format:out-inf-nan number width digits #f #f padch))
+
+ (else
+ (format:parse-float
+ (if (string? number) number (number->string number)) #t 0)
+ (if (<= (- format:fn-len format:fn-dot) digits)
+ (format:fn-zfill #f (- digits (- format:fn-len format:fn-dot)))
+ (format:fn-round digits))
+ (let ((numlen (+ format:fn-len 1)))
+ (if (or (not format:fn-pos?) (memq modifier '(at colon-at)))
+ (set! numlen (+ numlen 1)))
+ (if (and mindig (> mindig format:fn-dot))
+ (set! numlen (+ numlen (- mindig format:fn-dot))))
+ (if (and (= format:fn-dot 0) (not mindig))
+ (set! numlen (+ numlen 1)))
+ (if (< numlen width)
+ (case modifier
+ ((colon)
+ (if (not format:fn-pos?)
+ (format:out-char #\-))
+ (format:out-fill (- width numlen) (integer->char padch)))
+ ((at)
+ (format:out-fill (- width numlen) (integer->char padch))
+ (format:out-char (if format:fn-pos? #\+ #\-)))
+ ((colon-at)
+ (format:out-char (if format:fn-pos? #\+ #\-))
+ (format:out-fill (- width numlen) (integer->char padch)))
+ (else
+ (format:out-fill (- width numlen) (integer->char padch))
+ (if (not format:fn-pos?)
+ (format:out-char #\-))))
+ (if format:fn-pos?
+ (if (memq modifier '(at colon-at)) (format:out-char #\+))
+ (format:out-char #\-))))
+ (if (and mindig (> mindig format:fn-dot))
+ (format:out-fill (- mindig format:fn-dot) #\0))
+ (if (and (= format:fn-dot 0) (not mindig))
+ (format:out-char #\0))
+ (format:out-substr format:fn-str 0 format:fn-dot)
+ (format:out-char #\.)
+ (format:out-substr format:fn-str format:fn-dot format:fn-len)))))))
+
+ ; the flonum buffers
+
+ (format:fn-max 400) ; max. number of number digits
+ (format:fn-str #f) ; number buffer
+ (format:fn-len 0) ; digit length of number
+ (format:fn-dot #f) ; dot position of number
+ (format:fn-pos? #t) ; number positive?
+ (format:en-max 10) ; max. number of exponent digits
+ (format:en-str #f) ; exponent buffer
+ (format:en-len 0) ; digit length of exponent
+ (format:en-pos? #t) ; exponent positive?
+
+ (format:parse-float
+ (lambda (num-str fixed? scale)
+ (set! format:fn-pos? #t)
+ (set! format:fn-len 0)
+ (set! format:fn-dot #f)
+ (set! format:en-pos? #t)
+ (set! format:en-len 0)
+ (do ((i 0 (+ i 1))
+ (left-zeros 0)
+ (mantissa? #t)
+ (all-zeros? #t)
+ (num-len (string-length num-str))
+ (c #f)) ; current exam. character in num-str
+ ((= i num-len)
+ (if (not format:fn-dot)
+ (set! format:fn-dot format:fn-len))
+
+ (if all-zeros?
+ (begin
+ (set! left-zeros 0)
+ (set! format:fn-dot 0)
+ (set! format:fn-len 1)))
+
+ ;; now format the parsed values according to format's need
+
+ (if fixed?
+
+ (begin ; fixed format m.nnn or .nnn
+ (if (and (> left-zeros 0) (> format:fn-dot 0))
+ (if (> format:fn-dot left-zeros)
+ (begin ; norm 0{0}nn.mm to nn.mm
+ (format:fn-shiftleft left-zeros)
+ (set! format:fn-dot (- format:fn-dot left-zeros))
+ (set! left-zeros 0))
+ (begin ; normalize 0{0}.nnn to .nnn
+ (format:fn-shiftleft format:fn-dot)
+ (set! left-zeros (- left-zeros format:fn-dot))
+ (set! format:fn-dot 0))))
+ (if (or (not (= scale 0)) (> format:en-len 0))
+ (let ((shift (+ scale (format:en-int))))
+ (cond
+ (all-zeros? #t)
+ ((> (+ format:fn-dot shift) format:fn-len)
+ (format:fn-zfill
+ #f (- shift (- format:fn-len format:fn-dot)))
+ (set! format:fn-dot format:fn-len))
+ ((< (+ format:fn-dot shift) 0)
+ (format:fn-zfill #t (- (- shift) format:fn-dot))
+ (set! format:fn-dot 0))
+ (else
+ (if (> left-zeros 0)
+ (if (<= left-zeros shift) ; shift always > 0 here
+ (format:fn-shiftleft shift) ; shift out 0s
+ (begin
+ (format:fn-shiftleft left-zeros)
+ (set! format:fn-dot (- shift left-zeros))))
+ (set! format:fn-dot (+ format:fn-dot shift))))))))
+
+ (let ((negexp ; expon format m.nnnEee
+ (if (> left-zeros 0)
+ (- left-zeros format:fn-dot -1)
+ (if (= format:fn-dot 0) 1 0))))
+ (if (> left-zeros 0)
+ (begin ; normalize 0{0}.nnn to n.nn
+ (format:fn-shiftleft left-zeros)
+ (set! format:fn-dot 1))
+ (if (= format:fn-dot 0)
+ (set! format:fn-dot 1)))
+ (format:en-set (- (+ (- format:fn-dot scale) (format:en-int))
+ negexp))
+ (cond
+ (all-zeros?
+ (format:en-set 0)
+ (set! format:fn-dot 1))
+ ((< scale 0) ; leading zero
+ (format:fn-zfill #t (- scale))
+ (set! format:fn-dot 0))
+ ((> scale format:fn-dot)
+ (format:fn-zfill #f (- scale format:fn-dot))
+ (set! format:fn-dot scale))
+ (else
+ (set! format:fn-dot scale)))))
+ #t)
+
+ ;; do body
+ (set! c (string-ref num-str i)) ; parse the output of number->string
+ (cond ; which can be any valid number
+ ((char-numeric? c) ; representation of R4RS except
+ (if mantissa? ; complex numbers
+ (begin
+ (if (char=? c #\0)
+ (if all-zeros?
+ (set! left-zeros (+ left-zeros 1)))
+ (begin
+ (set! all-zeros? #f)))
+ (string-set! format:fn-str format:fn-len c)
+ (set! format:fn-len (+ format:fn-len 1)))
+ (begin
+ (string-set! format:en-str format:en-len c)
+ (set! format:en-len (+ format:en-len 1)))))
+ ((or (char=? c #\-) (char=? c #\+))
+ (if mantissa?
+ (set! format:fn-pos? (char=? c #\+))
+ (set! format:en-pos? (char=? c #\+))))
+ ((char=? c #\.)
+ (set! format:fn-dot format:fn-len))
+ ((char=? c #\e)
+ (set! mantissa? #f))
+ ((char=? c #\E)
+ (set! mantissa? #f))
+ ((char-whitespace? c) #t)
+ ((char=? c #\d) #t) ; decimal radix prefix
+ ((char=? c #\#) #t)
+ (else
+ (format:error "illegal character `~c' in number->string" c))))))
+
+ (format:en-int
+ (lambda () ; convert exponent string to integer
+ (if (= format:en-len 0)
+ 0
+ (do ((i 0 (+ i 1))
+ (n 0))
+ ((= i format:en-len)
+ (if format:en-pos?
+ n
+ (- n)))
+ (set! n (+ (* n 10) (- (char->integer (string-ref format:en-str i))
+ format:zero-ch)))))))
+
+ (format:en-set ; set exponent string number
+ (lambda (en)
+ (set! format:en-len 0)
+ (set! format:en-pos? (>= en 0))
+ (let ((en-str (number->string en)))
+ (do ((i 0 (+ i 1))
+ (en-len (string-length en-str))
+ (c #f))
+ ((= i en-len))
+ (set! c (string-ref en-str i))
+ (if (char-numeric? c)
+ (begin
+ (string-set! format:en-str format:en-len c)
+ (set! format:en-len (+ format:en-len 1))))))))
+
+ (format:fn-zfill ; fill current number string with 0s
+ (lambda (left? n)
+ (if (> (+ n format:fn-len) format:fn-max) ; from the left or right
+ (format:error "number is too long to format (enlarge format:fn-max)"))
+ (set! format:fn-len (+ format:fn-len n))
+ (if left?
+ (do ((i format:fn-len (- i 1))) ; fill n 0s to left
+ ((< i 0))
+ (string-set! format:fn-str i
+ (if (< i n)
+ #\0
+ (string-ref format:fn-str (- i n)))))
+ (do ((i (- format:fn-len n) (+ i 1))) ; fill n 0s to the right
+ ((= i format:fn-len))
+ (string-set! format:fn-str i #\0)))))
+
+ (format:fn-shiftleft ; shift left current number n positions
+ (lambda (n)
+ (if (> n format:fn-len)
+ (format:error "internal error in format:fn-shiftleft (~d,~d)"
+ n format:fn-len))
+ (do ((i n (+ i 1)))
+ ((= i format:fn-len)
+ (set! format:fn-len (- format:fn-len n)))
+ (string-set! format:fn-str (- i n) (string-ref format:fn-str i)))))
+
+ (format:fn-round ; round format:fn-str
+ (lambda (digits)
+ (set! digits (+ digits format:fn-dot))
+ (do ((i digits (- i 1)) ; "099",2 -> "10"
+ (c 5)) ; "023",2 -> "02"
+ ((or (= c 0) (< i 0)) ; "999",2 -> "100"
+ (if (= c 1) ; "005",2 -> "01"
+ (begin ; carry overflow
+ (set! format:fn-len digits)
+ (format:fn-zfill #t 1) ; add a 1 before fn-str
+ (string-set! format:fn-str 0 #\1)
+ (set! format:fn-dot (+ format:fn-dot 1)))
+ (set! format:fn-len digits)))
+ (set! c (+ (- (char->integer (string-ref format:fn-str i))
+ format:zero-ch) c))
+ (string-set! format:fn-str i (integer->char
+ (if (< c 10)
+ (+ c format:zero-ch)
+ (+ (- c 10) format:zero-ch))))
+ (set! c (if (< c 10) 0 1)))))
+
+ (format:fn-out
+ (lambda (modifier add-leading-zero?)
+ (if format:fn-pos?
+ (if (eq? modifier 'at)
+ (format:out-char #\+))
+ (format:out-char #\-))
+ (if (= format:fn-dot 0)
+ (if add-leading-zero?
+ (format:out-char #\0))
+ (format:out-substr format:fn-str 0 format:fn-dot))
+ (format:out-char #\.)
+ (format:out-substr format:fn-str format:fn-dot format:fn-len)))
+
+ (format:en-out
+ (lambda (edigits expch)
+ (format:out-char (if expch (integer->char expch) format:expch))
+ (format:out-char (if format:en-pos? #\+ #\-))
+ (if edigits
+ (if (< format:en-len edigits)
+ (format:out-fill (- edigits format:en-len) #\0)))
+ (format:out-substr format:en-str 0 format:en-len)))
+
+ (format:fn-strip ; strip trailing zeros but one
+ (lambda ()
+ (string-set! format:fn-str format:fn-len #\0)
+ (do ((i format:fn-len (- i 1)))
+ ((or (not (char=? (string-ref format:fn-str i) #\0))
+ (<= i format:fn-dot))
+ (set! format:fn-len (+ i 1))))))
+
+ (format:fn-zlead ; count leading zeros
+ (lambda ()
+ (do ((i 0 (+ i 1)))
+ ((or (= i format:fn-len)
+ (not (char=? (string-ref format:fn-str i) #\0)))
+ (if (= i format:fn-len) ; found a real zero
+ 0
+ i)))))
+
+
+;;; some global functions not found in SLIB
+
+ (string-capitalize-first ; "hello" -> "Hello"
+ (lambda (str)
+ (let ((cap-str (string-copy str)) ; "hELLO" -> "Hello"
+ (non-first-alpha #f) ; "*hello" -> "*Hello"
+ (str-len (string-length str))) ; "hello you" -> "Hello you"
+ (do ((i 0 (+ i 1)))
+ ((= i str-len) cap-str)
+ (let ((c (string-ref str i)))
+ (if (char-alphabetic? c)
+ (if non-first-alpha
+ (string-set! cap-str i (char-downcase c))
+ (begin
+ (set! non-first-alpha #t)
+ (string-set! cap-str i (char-upcase c))))))))))
+
+ ;; Aborts the program when a formatting error occures. This is a null
+ ;; argument closure to jump to the interpreters toplevel continuation.
+
+ (format:abort (lambda () (error "error in format"))))
+
+ (set! format:error-save format:error)
+ (set! format:fn-str (make-string format:fn-max)) ; number buffer
+ (set! format:en-str (make-string format:en-max)) ; exponent buffer
+ (apply format:format args)))
+
+;; Thanks to Shuji Narazaki
+(module-set! the-root-module 'format format)
projects / lilypond.git / blobdiff