I did in fact try installing readline-gpl (raco pkg install readline-gpl), but it didn’t change anything. Interestingly, the bug in #3223 persists for me, too. This suggests that I didn’t install or invoke it correctly. Do you need to run racket with any flag to make readline-gpl take its effect?
But yes, the problem is definitely due to readline. Sam suggested me to try racket -q which suppresses readline, and the result is that there’s no issue. On Thu, Jul 9, 2020 at 11:43 AM Philip McGrath <[email protected]> wrote: > On Thu, Jul 9, 2020 at 10:32 AM Sorawee Porncharoenwase < > [email protected]> wrote: > >> Racket REPL doesn’t handle unicode well. If you try (regexp-match? >> #px"^[a-zA-Z]+$" "héllo") in DrRacket, or write it as a program in a >> file and run it, you will find that it does evaluate to #f. >> > See this issue for workarounds, including installing the `readline-gpl` > package: https://github.com/racket/racket/issues/3223 > > But you may have some other issues: for me, `(regexp-match? > #px"^[a-zA-Z]+$" "h\U+FFC3\U+FFA9llo")` gives an error saying "read-syntax: > no hex digit following `\U`" > > For the original question: > > >> On Thu, Jul 9, 2020 at 7:19 AM Peter W A Wood <[email protected]> >> wrote: >> >>> I was experimenting with regular expressions to try to emulate the >>> Python isalpha() String method. >>> >> > You'd want to benchmark, but, for this purpose, I have a hunch you might > get better performance by using `in-string` with a `for/and` loop (which > can use unsafe operations internally)—probably especially so if you were > content to just test `char-alphabetic?`, which follows Unicode's definition > of "alphabetic" rather that Python's idiosyncratic one. Here's an example: > > #lang racket >> >> (module+ test >> (require rackunit)) >> >> (define (char-letter? ch) >> ;; not the same as `char-alphabetic?`: see >> ;; https://docs.python.org/3/library/stdtypes.html#str.isalpha >> (case (char-general-category ch) >> [(lm lt lu ll lo) #t] >> [else #f])) >> >> (define (string-is-alpha? str) >> (for/and ([ch (in-string str)]) >> (char-letter? ch))) >> >> (module+ test >> (check-true (string-is-alpha? "hello")) >> (check-false (string-is-alpha? "h1llo")) >> (check-true (string-is-alpha? "héllo"))) >> > > -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/racket-users/CADcuegsvwBVDhnjtR5Gu6itoYWQPiiQHdwcZnaMv1Qvne2dAVg%40mail.gmail.com.
