racket/collects/scribblings/foreign/vector.scrbl
Michael Filonenko 840fc9c657 full unboxing for extflonums, plus `ffi/unsafe' support
Includes a repair for floating-point `min' and `max' that affects all
x86 builds that use SSE arithmetic, leaving the (otherwise unused)
floating-point stack in a bad state, which might have affected
x87-using C/foreign libraries running alongside Racket.
2013-02-15 12:15:34 -07:00

120 lines
5.7 KiB
Racket

#lang scribble/doc
@(require "utils.rkt"
(only-in scribble/decode make-splice)
scribble/racket
(for-label racket/extflonum))
@title[#:tag "homogeneous-vectors"]{Safe Homogenous Vectors}
@defmodule[ffi/vector]
Homogenous vectors are similar to C vectors (see
@secref["foreign:cvector"]), except that they define different types
of vectors, each with a fixed element type. An exception is the
@racketidfont{u8} family of bindings, which are just aliases for
byte-string bindings; for example, @racket[make-u8vector] is an alias
for @racket[make-bytes].
@(begin
(require (for-syntax scheme/base))
(define-syntax (srfi-4-vector stx)
(syntax-case stx ()
[(_ id elem number?)
#'(srfi-4-vector/desc id elem number? make-splice
"Like " (racket make-vector) ", etc., but for " (racket elem) " elements.")]))
(define-syntax (srfi-4-vector/desc stx)
(syntax-case stx ()
[(_ id elem as-number? extra desc ...)
(let ([mk
(lambda l
(datum->syntax
#'id
(string->symbol
(apply string-append
(map (lambda (i)
(if (identifier? i)
(symbol->string (syntax-e i))
i))
l)))
#'id))])
(with-syntax ([make (mk "make-" #'id "vector")]
[vecr (mk #'id "vector")]
[? (mk #'id "vector?")]
[length (mk #'id "vector-length")]
[ref (mk #'id "vector-ref")]
[! (mk #'id "vector-set!")]
[list-> (mk "list->" #'id "vector")]
[->list (mk #'id "vector->list")]
[->cpointer (mk #'id "vector->cpointer")]
[_vec (mk "_" #'id "vector")])
#`(let-syntax ([number? (make-element-id-transformer
(lambda (stx)
#'(racket as-number?)))])
(list
(defproc* ([(make [len exact-nonnegative-integer?]) ?]
[(vecr [val number?] (... ...)) ?]
[(? [v any/c]) boolean?]
[(length [vec ?]) exact-nonnegative-integer?]
[(ref [vec ?] [k exact-nonnegative-integer?]) number?]
[(! [vec ?] [k exact-nonnegative-integer?] [val number?]) void?]
[(list-> [lst (listof number?)]) ?]
[(->list [vec ?]) (listof number?)]
[(->cpointer [vec ?]) cpointer?])
desc ...
(extra
(list
" The " (racket ->cpointer)
" function extracts a plain pointer to the underlying array.")))
;; Big pain: make up relatively-correct source locations
;; for pieces in the _vec definition:
(defform* [#,(datum->syntax
#'_vec
(cons #'_vec
(let loop ([l '(mode maybe-len)]
[col (+ (syntax-column #'_vec)
(syntax-span #'_vec)
1)]
[pos (+ (syntax-position #'_vec)
(syntax-span #'_vec)
1)])
(if (null? l)
null
(let ([span (string-length (symbol->string (car l)))])
(cons (datum->syntax
#'_vec
(car l)
(list (syntax-source #'_vec)
(syntax-line #'_vec)
col
pos
span))
(loop (cdr l)
(+ col 1 span)
(+ pos 1 span)))))))
(list (syntax-source #'_vec)
(syntax-line #'_vec)
(sub1 (syntax-column #'vec))
(sub1 (syntax-position #'vec))
10))
_vec]
"Like " (racket _cvector) ", but for vectors of "
(racket elem) " elements.")))))])))
@srfi-4-vector/desc[u8 _uint8 byte? (lambda (x) (make-splice null))]{
Like @racket[_cvector], but for vectors of @racket[_uint8] elements. These are
aliases for @racketidfont{byte} operations, where @racket[u8vector->cpointer]
is the identity function.}
@srfi-4-vector[s8 _int8 (integer-in -128 127)]
@srfi-4-vector[s16 _int16 (integer-in -32768 32767)]
@srfi-4-vector[u16 _uint16 (integer-in 0 65535)]
@srfi-4-vector[s32 _int32 (integer-in -2147483648 2147483647)]
@srfi-4-vector[u32 _uint32 (integer-in 0 4294967295)]
@srfi-4-vector[s64 _int64 (integer-in -9223372036854775808 9223372036854775807)]
@srfi-4-vector[u64 _uint64 (integer-in 0 18446744073709551615)]
@srfi-4-vector[f32 _float real?]
@srfi-4-vector[f64 _double* real?]
@srfi-4-vector[f80 _longdouble extflonum?]