Re: [racket-dev] [plt] Push #20578: master branch updated
Just using the core of even-read didn't work. It would start to read after parse-statement had returned and then my parser would just sit there because the port wasn't returning EOF. I think it is a bug. Jay On Fri, Jun 25, 2010 at 10:44 PM, Eli Barzilay e...@barzilay.org wrote: On Jun 26, j...@racket-lang.org wrote: + ; XXX This is almost certainly wrong. + (define (even-read src ip) + (begin0 + (parameterize ([current-source-name src]) + (datum-syntax #f (parse-statement ip))) + (current-read-interaction odd-read))) + (define (odd-read src ip) + (current-read-interaction even-read) + eof) + + (current-read-interaction + even-read)) This is not just wrong -- it is likely to break things randomly. Something like -- if you happen to invoke the datalog reader indirectly (like just `read' a file in the language), you'd end up with one of these readers as a side-effect. This is exactly how the scribble/text language messed things up in a very confusing way: by banging `current-print' to do its own thing. -- ((lambda (x) (x x)) (lambda (x) (x x))) Eli Barzilay: http://barzilay.org/ Maze is Life! -- Jay McCarthy j...@cs.byu.edu Assistant Professor / Brigham Young University http://teammccarthy.org/jay The glory of God is Intelligence - DC 93 _ For list-related administrative tasks: http://lists.racket-lang.org/listinfo/dev
Re: [racket-dev] [plt] Push #20578: master branch updated
It should be set by the 'configure-runtime thunk (from module-language-info), right? (I'm not sure about the bug, tho.) Robby On Sat, Jun 26, 2010 at 8:47 AM, Jay McCarthy jay.mccar...@gmail.com wrote: Just using the core of even-read didn't work. It would start to read after parse-statement had returned and then my parser would just sit there because the port wasn't returning EOF. I think it is a bug. Jay On Fri, Jun 25, 2010 at 10:44 PM, Eli Barzilay e...@barzilay.org wrote: On Jun 26, j...@racket-lang.org wrote: + ; XXX This is almost certainly wrong. + (define (even-read src ip) + (begin0 + (parameterize ([current-source-name src]) + (datum-syntax #f (parse-statement ip))) + (current-read-interaction odd-read))) + (define (odd-read src ip) + (current-read-interaction even-read) + eof) + + (current-read-interaction + even-read)) This is not just wrong -- it is likely to break things randomly. Something like -- if you happen to invoke the datalog reader indirectly (like just `read' a file in the language), you'd end up with one of these readers as a side-effect. This is exactly how the scribble/text language messed things up in a very confusing way: by banging `current-print' to do its own thing. -- ((lambda (x) (x x)) (lambda (x) (x x))) Eli Barzilay: http://barzilay.org/ Maze is Life! -- Jay McCarthy j...@cs.byu.edu Assistant Professor / Brigham Young University http://teammccarthy.org/jay The glory of God is Intelligence - DC 93 _ For list-related administrative tasks: http://lists.racket-lang.org/listinfo/dev _ For list-related administrative tasks: http://lists.racket-lang.org/listinfo/dev
Re: [racket-dev] [plt] Push #20578: master branch updated
You are right. I used it and it works. Nice! Jay On Sat, Jun 26, 2010 at 4:58 PM, Robby Findler ro...@eecs.northwestern.edu wrote: It should be set by the 'configure-runtime thunk (from module-language-info), right? (I'm not sure about the bug, tho.) Robby On Sat, Jun 26, 2010 at 8:47 AM, Jay McCarthy jay.mccar...@gmail.com wrote: Just using the core of even-read didn't work. It would start to read after parse-statement had returned and then my parser would just sit there because the port wasn't returning EOF. I think it is a bug. Jay On Fri, Jun 25, 2010 at 10:44 PM, Eli Barzilay e...@barzilay.org wrote: On Jun 26, j...@racket-lang.org wrote: + ; XXX This is almost certainly wrong. + (define (even-read src ip) + (begin0 + (parameterize ([current-source-name src]) + (datum-syntax #f (parse-statement ip))) + (current-read-interaction odd-read))) + (define (odd-read src ip) + (current-read-interaction even-read) + eof) + + (current-read-interaction + even-read)) This is not just wrong -- it is likely to break things randomly. Something like -- if you happen to invoke the datalog reader indirectly (like just `read' a file in the language), you'd end up with one of these readers as a side-effect. This is exactly how the scribble/text language messed things up in a very confusing way: by banging `current-print' to do its own thing. -- ((lambda (x) (x x)) (lambda (x) (x x))) Eli Barzilay: http://barzilay.org/ Maze is Life! -- Jay McCarthy j...@cs.byu.edu Assistant Professor / Brigham Young University http://teammccarthy.org/jay The glory of God is Intelligence - DC 93 _ For list-related administrative tasks: http://lists.racket-lang.org/listinfo/dev -- Jay McCarthy j...@cs.byu.edu Assistant Professor / Brigham Young University http://teammccarthy.org/jay The glory of God is Intelligence - DC 93 _ For list-related administrative tasks: http://lists.racket-lang.org/listinfo/dev
