add an unlimit word, refactor limited-streams, better docs

db4
Doug Coleman 2009-01-20 15:42:41 -06:00
parent 57ecdbe2c3
commit 9a06ce94a5
3 changed files with 50 additions and 26 deletions

View File

@ -5,16 +5,23 @@ IN: io.streams.limited
HELP: <limited-stream>
{ $values
{ "stream" "an input stream" } { "limit" integer }
{ "stream" "an input stream" } { "limit" integer } { "mode" "a " { $link limited-stream } " mode singleton" }
{ "stream'" "an input stream" }
}
{ $description "Constructs a new " { $link limited-stream } " from an existing stream. Upon exhaustion, the stream will throw an error by default." }
{ $description "Constructs a new " { $link limited-stream } " from an existing stream. User code should use " { $link limit } " or " { $link limit-input } "." } ;
HELP: limit
{ $values
{ "stream" "an input stream" } { "limit" integer } { "mode" "a " { $link limited-stream } " mode singleton" }
{ "stream'" "a stream" }
}
{ $description "Changes a decoder's stream to be a limited stream, or wraps " { $snippet "stream" } " in a " { $link limited-stream } "." }
{ $examples "Throwing an exception:"
{ $example
"USING: continuations io io.streams.limited io.streams.string"
"kernel prettyprint ;"
"["
" \"123456\" <string-reader> 3 <limited-stream>"
" \"123456\" <string-reader> 3 stream-throws limit"
" 100 swap stream-read ."
"] [ ] recover ."
"T{ limit-exceeded }"
@ -23,32 +30,34 @@ HELP: <limited-stream>
{ $example
"USING: accessors continuations io io.streams.limited"
"io.streams.string kernel prettyprint ;"
"\"123456\" <string-reader> 3 <limited-stream>"
"stream-eofs >>mode"
"\"123456\" <string-reader> 3 stream-eofs limit"
"100 swap stream-read ."
"\"123\""
}
} ;
HELP: limit
HELP: unlimit
{ $values
{ "stream" "a stream" } { "limit" integer }
{ "stream" "an input stream" }
{ "stream'" "a stream" }
}
{ $description "Changes a decoder's stream to be a limited stream, or wraps " { $snippet "stream" } " in a " { $link limited-stream } "." } ;
{ $description "Returns the underlying stream of a limited stream." } ;
HELP: limited-stream
{ $values
{ "value" "a limited-stream class" }
}
{ $description "Limited streams wrap other streams, changing their behavior to throw an exception or return " { $link f } " upon exhaustion. The default behavior is to throw an exception." } ;
{ $description "Limited streams wrap other streams, changing their behavior to throw an exception or return " { $link f } " upon exhaustion." } ;
HELP: limit-input
{ $values
{ "limit" integer }
{ "limit" integer } { "mode" "a " { $link limited-stream } " mode singleton" }
}
{ $description "Wraps the current " { $link input-stream } " in a " { $link limited-stream } "." } ;
HELP: unlimit-input
{ $description "Returns the underlying stream of the limited-stream stored in " { $link input-stream } "." } ;
HELP: stream-eofs
{ $values
{ "value" "a " { $link limited-stream } " mode singleton" }
@ -64,13 +73,15 @@ HELP: stream-throws
{ stream-eofs stream-throws } related-words
ARTICLE: "io.streams.limited" "Limited input streams"
"The " { $vocab-link "io.streams.limited" } " vocabulary wraps a stream to behave as if it had only a limited number of bytes, either throwing an error or returning " { $link f } " upon reaching the end. The default behavior is to throw an error." $nl
"Wrap an existing stream in a limited stream:"
{ $subsection <limited-stream> }
"The " { $vocab-link "io.streams.limited" } " vocabulary wraps a stream to behave as if it had only a limited number of bytes, either throwing an error or returning " { $link f } " upon reaching the end." $nl
"Wrap a stream in a limited stream:"
{ $subsection limit }
"Wrap the current " { $link input-stream } " in a limited stream:"
{ $subsection limit-input }
"Unlimits a limited stream:"
{ $subsection unlimit }
"Unlimits the current " { $link input-stream } ":"
{ $subsection limit-input }
"Make a limited stream throw an exception on exhaustion:"
{ $subsection stream-throws }
"Make a limited stream return " { $link f } " on exhaustion:"

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@ -8,7 +8,7 @@ IN: io.streams.limited.tests
ascii encode binary <byte-reader> "data" set
] unit-test
[ ] [ "data" get 24 <limited-stream> "limited" set ] unit-test
[ ] [ "data" get 24 stream-throws <limited-stream> "limited" set ] unit-test
[ CHAR: h ] [ "limited" get stream-read1 ] unit-test
@ -25,7 +25,7 @@ IN: io.streams.limited.tests
ascii encode binary <byte-reader> "data" set
] unit-test
[ ] [ "data" get 7 <limited-stream> "limited" set ] unit-test
[ ] [ "data" get 7 stream-throws <limited-stream> "limited" set ] unit-test
[ "abc" CHAR: \n ] [ "\n" "limited" get stream-read-until [ >string ] dip ] unit-test
@ -34,22 +34,28 @@ IN: io.streams.limited.tests
[ "he" CHAR: l ] [
B{ CHAR: h CHAR: e CHAR: l CHAR: l CHAR: o }
ascii <byte-reader> [
5 limit-input
5 stream-throws limit-input
"l" read-until
] with-input-stream
] unit-test
[ CHAR: a ]
[ "a" <string-reader> 1 <limited-stream> stream-read1 ] unit-test
[ "a" <string-reader> 1 stream-eofs <limited-stream> stream-read1 ] unit-test
[ "abc" ]
[
"abc" <string-reader> 3 <limited-stream> stream-eofs >>mode
"abc" <string-reader> 3 stream-eofs <limited-stream>
4 swap stream-read
] unit-test
[ f ]
[
"abc" <string-reader> 3 <limited-stream> stream-eofs >>mode
"abc" <string-reader> 3 stream-eofs <limited-stream>
4 over stream-read drop 10 swap stream-read
] unit-test
[ t ]
[
"abc" <string-reader> 3 stream-eofs limit unlimit
"abc" <string-reader> =
] unit-test

View File

@ -9,20 +9,27 @@ TUPLE: limited-stream stream count limit mode ;
SINGLETONS: stream-throws stream-eofs ;
: <limited-stream> ( stream limit -- stream' )
: <limited-stream> ( stream limit mode -- stream' )
limited-stream new
swap >>mode
swap >>limit
swap >>stream
0 >>count
stream-throws >>mode ;
0 >>count ;
GENERIC# limit 1 ( stream limit -- stream' )
GENERIC# limit 2 ( stream limit mode -- stream' )
M: decoder limit [ clone ] dip [ limit ] curry change-stream ;
M: decoder limit ( stream limit mode -- stream' )
[ clone ] 2dip '[ _ _ limit ] change-stream ;
M: object limit <limited-stream> ;
M: object limit ( stream limit mode -- stream' )
<limited-stream> ;
: limit-input ( limit -- ) input-stream [ swap limit ] change ;
: unlimit ( stream -- stream' )
[ stream>> ] change-stream ;
: limit-input ( limit mode -- ) input-stream [ -rot limit ] change ;
: unlimit-input ( -- ) input-stream [ unlimit ] change ;
ERROR: limit-exceeded ;