How did you measure this performance increase? It would have been better to commit a stress test too.
On Wed, Nov 7, 2012 at 4:10 PM, <d...@racket-lang.org> wrote: > dyoo has updated `master' from 741be85f07 to 5cb2f3eb58. > http://git.racket-lang.org/plt/741be85f07..5cb2f3eb58 > > =====[ 4 Commits ]====================================================== > Directory summary: > 100.0% collects/xml/private/ > > ~~~~~~~~~~ > > fb3a95f Danny Yoo <d...@racket-lang.org> 2012-11-07 15:32 > : > | Replace fprintf with explicit display for performance. > | > | Replace fprintf with explicit display for performance. > : > M collects/xml/private/xexpr.rkt | 16 ++++++++++++---- > > ~~~~~~~~~~ > > 6d18928 Danny Yoo <d...@racket-lang.org> 2012-11-07 15:39 > : > | Add let loop for recursion and slight performance increase. > : > M collects/xml/private/xexpr.rkt | 115 > +++++++++++++++++++------------------- > > ~~~~~~~~~~ > > 40116eb Danny Yoo <d...@racket-lang.org> 2012-11-07 15:42 > : > | Lift out empty-tag-shorthand parameter lookup out of the hot spot. > : > M collects/xml/private/xexpr.rkt | 6 +++--- > > ~~~~~~~~~~ > > 5cb2f3e Danny Yoo <d...@racket-lang.org> 2012-11-07 16:03 > : > | Avoid regexp-replace* unless the string really contains escapable > characters. > : > M collects/xml/private/writer.rkt | 8 ++++++++ > M collects/xml/private/xexpr.rkt | 4 ++-- > > =====[ Overall Diff ]=================================================== > > collects/xml/private/writer.rkt > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > --- OLD/collects/xml/private/writer.rkt > +++ NEW/collects/xml/private/writer.rkt > @@ -168,7 +168,15 @@ > (define (escape x table) > (regexp-replace* table x replace-escaped)) > > +(define (display/escape x table out) > + (cond [(regexp-match table x) > + (display (escape x table) out)] > + [else > + (display x out)])) > + > + > (provide escape > + display/escape > escape-table > escape-attribute-table > lowercase-symbol > > collects/xml/private/xexpr.rkt > ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > --- OLD/collects/xml/private/xexpr.rkt > +++ NEW/collects/xml/private/xexpr.rkt > @@ -120,52 +120,61 @@ > [write-xexpr (->* (xexpr/c) (output-port?) void)] ) > > (define (write-xexpr x [out (current-output-port)]) > - (cond > - ; Element > - [(cons? x) > - (define name (car x)) > - (define-values (attrs content) > - (if (and (pair? (cdr x)) > - (or (null? (cadr x)) > - (and (pair? (cadr x)) (pair? (caadr x))))) > - (values (cadr x) (cddr x)) > - (values null (cdr x)))) > - ; Write opening tag > - (display "<" out) > - (display name out) > - ; Write attributes > - (for ([att (in-list attrs)]) > - (fprintf out " ~a=\"~a\"" (car att) > - (escape (cadr att) escape-attribute-table))) > - ; Write end of opening tag > - (if (and (null? content) > - (let ([short (empty-tag-shorthand)]) > + (define short (empty-tag-shorthand)) > + (let loop ([x x]) > + (cond > + ; Element > + [(cons? x) > + (define name (car x)) > + (define-values (attrs content) > + (if (and (pair? (cdr x)) > + (or (null? (cadr x)) > + (and (pair? (cadr x)) (pair? (caadr x))))) > + (values (cadr x) (cddr x)) > + (values null (cdr x)))) > + ; Write opening tag > + (display "<" out) > + (display name out) > + ; Write attributes > + (for ([att (in-list attrs)]) > + (display " " out) > + (display (car att) out) > + (display "=" out) > + (display "\"" out) > + (display/escape (cadr att) escape-attribute-table out) > + (display "\"" out)) > + ; Write end of opening tag > + (if (and (null? content) > (case short > - [(always) #t] > - [(never) #f] > - [else (memq (lowercase-symbol name) short)]))) > - (display " />" out) > - (begin > - (display ">" out) > - ; Write body > - (for ([xe (in-list content)]) > - (write-xexpr xe out)) > - ; Write closing tag > - (display "</" out) > - (display name out) > - (display ">" out)))] > - ; PCData > - [(string? x) > - (display (escape x escape-table) out)] > - ; Entities > - [(symbol? x) > - (fprintf out "&~a;" x)] > - [(valid-char? x) > - (fprintf out "&#~a;" x)] > - ; Embedded XML > - [(cdata? x) > - (write-xml-cdata x 0 void out)] > - [(comment? x) > - (write-xml-comment x 0 void out)] > - [(p-i? x) > - (write-xml-p-i x 0 void out)])) > + [(always) #t] > + [(never) #f] > + [else (memq (lowercase-symbol name) short)])) > + (display " />" out) > + (begin > + (display ">" out) > + ; Write body > + (for ([xe (in-list content)]) > + (loop xe)) > + ; Write closing tag > + (display "</" out) > + (display name out) > + (display ">" out)))] > + ; PCData > + [(string? x) > + (display/escape x escape-table out)] > + ; Entities > + [(symbol? x) > + (display "&" out) > + (display x out) > + (display ";" out)] > + [(valid-char? x) > + (display "&#" out) > + (display x out) > + (display ";" out)] > + ; Embedded XML > + [(cdata? x) > + (write-xml-cdata x 0 void out)] > + [(comment? x) > + (write-xml-comment x 0 void out)] > + [(p-i? x) > + (write-xml-p-i x 0 void out)]))) -- Jay McCarthy <j...@cs.byu.edu> Assistant Professor / Brigham Young University http://faculty.cs.byu.edu/~jay "The glory of God is Intelligence" - D&C 93 _________________________ Racket Developers list: http://lists.racket-lang.org/dev
