Minor pickinesses.
This commit is contained in:
parent
7ffe9f2612
commit
d67396cbb1
|
@ -7,11 +7,12 @@
|
||||||
@title[#:tag "stringport"]{String Ports}
|
@title[#:tag "stringport"]{String Ports}
|
||||||
|
|
||||||
A @deftech{string port} reads or writes from a @tech{byte string}. An
|
A @deftech{string port} reads or writes from a @tech{byte string}. An
|
||||||
input @tech{string port} can be created from either a @tech{byte string} or a
|
input @tech{string port} can be created from either a @tech{byte string}
|
||||||
@tech{string}; in the latter case, the @tech{string} is effectively converted to
|
or a @tech{string}; in the latter case, the @tech{string} is effectively
|
||||||
a @tech{byte string} using @racket[string->bytes/utf-8]. An output @tech{string port}
|
converted to a @tech{byte string} using @racket[string->bytes/utf-8]. An
|
||||||
collects output into a @tech{byte string}, but @racket[get-output-string]
|
output @tech{string port} collects output into a @tech{byte string}, but
|
||||||
conveniently converts the accumulated bytes to a @tech{string}.
|
@racket[get-output-string] conveniently converts the accumulated bytes
|
||||||
|
to a @tech{string}.
|
||||||
|
|
||||||
Input and output @tech{string ports} do not need to be explicitly
|
Input and output @tech{string ports} do not need to be explicitly
|
||||||
closed. The @racket[file-position] procedure works for @tech{string
|
closed. The @racket[file-position] procedure works for @tech{string
|
||||||
|
@ -21,31 +22,30 @@ ports} in position-setting mode.
|
||||||
|
|
||||||
@defproc[(open-input-bytes [bstr bytes?] [name any/c 'string]) input-port?]{
|
@defproc[(open-input-bytes [bstr bytes?] [name any/c 'string]) input-port?]{
|
||||||
|
|
||||||
Creates an input @tech{string port} that reads characters from @racket[bstr] (see
|
Creates an input @tech{string port} that reads characters from
|
||||||
@secref["bytestrings"]). Modifying @racket[bstr] afterward does not
|
@racket[bstr] (see @secref["bytestrings"]). Modifying @racket[bstr]
|
||||||
affect the byte stream produced by the port. The optional
|
afterward does not affect the byte stream produced by the port. The
|
||||||
@racket[name] argument is used as the name for the returned port.}
|
optional @racket[name] argument is used as the name for the returned
|
||||||
|
port.}
|
||||||
|
|
||||||
@examples[
|
@examples[#:eval sp-eval
|
||||||
#:eval sp-eval
|
|
||||||
(define sp (open-input-bytes #"(apples 42 day)"))
|
(define sp (open-input-bytes #"(apples 42 day)"))
|
||||||
(define sexp1 (read sp))
|
(define sexp1 (read sp))
|
||||||
(first sexp1)
|
(first sexp1)
|
||||||
(rest sexp1)
|
(rest sexp1)
|
||||||
(define sp (open-input-bytes #"the cow jumped over the moon\nthe little dog\n"))
|
(read-line (open-input-bytes
|
||||||
(read-line sp)
|
#"the cow jumped over the moon\nthe little dog\n"))
|
||||||
]
|
]
|
||||||
|
|
||||||
@refalso["strings"]{strings}
|
@refalso["strings"]{strings}
|
||||||
|
|
||||||
@defproc[(open-input-string [str string?] [name any/c 'string]) input-port?]{
|
@defproc[(open-input-string [str string?] [name any/c 'string]) input-port?]{
|
||||||
|
|
||||||
Creates an input @tech{string port} that reads bytes from the UTF-8 encoding (see
|
Creates an input @tech{string port} that reads bytes from the UTF-8
|
||||||
@secref["encodings"]) of @racket[str]. The optional @racket[name]
|
encoding (see @secref["encodings"]) of @racket[str]. The optional
|
||||||
argument is used as the name for the returned port.}
|
@racket[name] argument is used as the name for the returned port.}
|
||||||
|
|
||||||
@examples[
|
@examples[#:eval sp-eval
|
||||||
#:eval sp-eval
|
|
||||||
(define sp (open-input-string "(λ (x) x)"))
|
(define sp (open-input-string "(λ (x) x)"))
|
||||||
(read sp)
|
(read sp)
|
||||||
(define names (open-input-string "Günter Harder\nFrédéric Paulin\n"))
|
(define names (open-input-string "Günter Harder\nFrédéric Paulin\n"))
|
||||||
|
@ -54,8 +54,8 @@ argument is used as the name for the returned port.}
|
||||||
|
|
||||||
@defproc[(open-output-bytes [name any/c 'string]) output-port?]{
|
@defproc[(open-output-bytes [name any/c 'string]) output-port?]{
|
||||||
|
|
||||||
Creates an output @tech{string port} that accumulates the output into a byte
|
Creates an output @tech{string port} that accumulates the output into a
|
||||||
string. The optional @racket[name] argument is used as the name for
|
byte string. The optional @racket[name] argument is used as the name for
|
||||||
the returned port.}
|
the returned port.}
|
||||||
|
|
||||||
@examples[ #:eval sp-eval
|
@examples[ #:eval sp-eval
|
||||||
|
@ -95,13 +95,13 @@ same as @racket[open-output-bytes].}
|
||||||
[end-pos exact-nonnegative-integer? #f])
|
[end-pos exact-nonnegative-integer? #f])
|
||||||
bytes?]{
|
bytes?]{
|
||||||
|
|
||||||
Returns the bytes accumulated in the @tech{string port} @racket[out] so far in a
|
Returns the bytes accumulated in the @tech{string port} @racket[out] so
|
||||||
freshly allocated @tech{byte string} (including any bytes written after the
|
far in a freshly allocated @tech{byte string} (including any bytes
|
||||||
port's current position, if any). The @racket[out] port must be an
|
written after the port's current position, if any). The @racket[out]
|
||||||
output @tech{string port} produced by @racket[open-output-bytes] (or
|
port must be an output @tech{string port} produced by
|
||||||
@racket[open-output-string]) or a structure whose
|
@racket[open-output-bytes] (or @racket[open-output-string]) or a
|
||||||
@racket[prop:output-port] property refers to such an output port
|
structure whose @racket[prop:output-port] property refers to such an
|
||||||
(transitively).
|
output port (transitively).
|
||||||
|
|
||||||
If @racket[reset?] is true, then all bytes are removed from the port,
|
If @racket[reset?] is true, then all bytes are removed from the port,
|
||||||
and the port's position is reset to @racket[0]; if @racket[reset?] is
|
and the port's position is reset to @racket[0]; if @racket[reset?] is
|
||||||
|
|
Loading…
Reference in New Issue
Block a user