Saul, Just a couple of quick additional comments on your feedback:
I would like to refer you to http://docs.gimp.org/2.8/en/gimp-using-script-fu-tutorial-identifier.htmland the examples in sections 3.2.1 and 3.2.6 with respect to your stylistic comments #2 and #4 about parenthesis placement. The coding style in these sections looks more like mine. You made a comment about the script-fu-register block "... For this reason it has been decided that this description should be limited to a single line of text[2]. ..." . The site http://www.gimp.org/tutorials/Basic_Scheme/section 5 would have been a much more effective place to reflect that decision. I did try again and was able to get the web site you mentioned to come up and found a long 7 year old discussion thread about blurbs. The thing is, no one would think to read through this to see if a decision or standard was ever reached. If the decision is important enough to matter, it needs to be documented on a web site that people are likely to find based on getting there with a search engine. Thanks, Stephen On Tue, Feb 25, 2014 at 5:40 AM, Saul Goode <s...@crazyauntgail.com> wrote: > On Mon, Feb 24, 2014 at 9:36 PM, Pat David <patdavid gmail com> wrote: > Could someone with a better grasp of the material chime in to help iron > this out so that we can possibly include it as either a tutorial or wiki > material? > > > > I should like to offer some comments on the Script-fu material presented > in the AutomatedJpgToXcf tutorial on wgo[1]. > > > The first requirement ("The script needs to be available and run when > there is no image open" is only half correct. While it is true that the > script needs to be available when no image is open, there is no need -- or > benefit -- to prevent the script from running when an image is open. > > > The script could be simplified by using the Script-fu constant > DIR-SEPARATOR when constructing the pathnames. There is no need to > determine the host operating system. > > The script uses 'file-glob' to build a list of the names of pre-existing > files in the target directory, then checks whether the filename of the file > being saved is in that list before saving. Since GIMP 2.4 there has been a > 'file-exists?' procedure available that obviates the need for this code. > > With regard to the description supplied in the 'script-fu-register' block, > while it is true that this description appears in the Procedural DataBase > browser, more importantly it appears in the status line and infobox popup > when the mouse is hovered over the menu command. For this reason it has > been decided that this description should be limited to a single line of > text[2]. By convention, this text should describe what the command will do > when executed ("Copy all JPEG files in a directory as XCF files"). > > The remainder of my critique addresses the issue of stylistic choices and > some areas where the example script deviates from conventional Scheme > programming style. > > 1) Boolean procedures and variables should end with a question mark (e.g., > "linux?", not "isLinux"). > > > 2) As a general rule, white spaces should not appear after an open > parethesis or before a closing one. > > > 3) The first part of a compound expression should rarely be followed by a > newline; when it is, the remainder of the expression should be indented > from the start of that compound expression. > > For example: > (if (zero? (length string)) > or: > (if (zero? > (length string)) > > but not: > (if (zero? > (length string)) > > > 4) The closing parenthesis of a multi-line expression should appear either > on the same line as the last subexpression or nested to the same level as > the subexpressions. It should never appear directly beneath the opening > parenthesis of the expression. > > > For example: > (begin > (display "Hello, world") > (newline)) > or: > > (begin > (display "Hello, world") > (newline) > ) > not: > > (begin > (display "Hello, world") > (newline) > ) > > 5) The convention in Scheme is to use hyphens to separate words within the > names of constants and variables, as opposed to CamelCase or the use of > under_scores. This practice is re-enforced in Script-fu by virtue of all > Script-fu constants and PDB procedures following this naming convention > (despite the actual names in the database employing underscores). > > > > While all of these points might to some degree be considered mere > stylistic preferences, following the idiomatic conventions of a particular > programming language makes the program easier to read and understand. While > some of the scripts that ship with GIMP may deviate from some of these > conventions, official GIMP tutorials should avoid making the same mistake. > To quote Kernighan and Pike, "The purpose of style is to make the code > easy to read for yourself and others, and good style is crucial to good > programming." > > I apologize if this all seems overly negative and critical. It just seems > to me that in order to address a lack of good documentation about scripting > in GIMP, it is necessary for the documentation that is provided itself be > of a high caliber. > > > > Finally, I am inclosing my own version of the same procedure (I omitted > the registration block), incorporating some of the above commentary: > > (define (script-fu-example-jpg-to-xcf source-directory target-directory) > (let ((pattern (string-append source-directory > DIR-SEPARATOR > "*.[jJ][pP][gG]" ))) > (let loop ((source-files (cadr (file-glob pattern 1)))) > (unless (null? source-files) > (let* ((source-name (car source-files)) > (basename (car (last (strbreakup source-name > DIR-SEPARATOR)))) > (basename-without-extension > (unbreakupstr (butlast (strbreakup basename ".")) > "." )) > (target-name (string-append target-directory > DIR-SEPARATOR > basename-without-extension > ".xcf")) ) > (unless (file-exists? target-name) > (let ((image (catch #f (car (file-jpeg-load RUN-NONINTERACTIVE > source-name > source-name ))))) > (if image > (begin > (gimp-xcf-save RUN-NONINTERACTIVE image -1 target-name > target-name) > (gimp-image-delete image) )))) > (loop (cdr source-files)))))) > > > > > [1] http://www.gimp.org/tutorials/AutomatedJpgToXcf/ > > [2] > http://www.gimpusers.com/forums/gimp-developer/5624-script-fu-procedure-blurb-review > > _______________________________________________ > gimp-web-list mailing list > gimp-web-list@gnome.org > https://mail.gnome.org/mailman/listinfo/gimp-web-list > -- Stephen Kiel 26602 Strafford Mission Viejo, CA 92692 *Mobile/SMS (949) 702-1993* Home (949) 367-2915 snick.k...@gmail.com http://stephenkiel.blogspot.com/ _______________________________________________ gimp-web-list mailing list gimp-web-list@gnome.org https://mail.gnome.org/mailman/listinfo/gimp-web-list
