On Sat, 20 Oct 2007 11:02:34 -0500 Larry Garfield <larry@garfieldtech.com> wrote:
On Friday 19 October 2007, Ivan Sergio Borgonovo wrote:
On Fri, 19 Oct 2007 11:20:27 -0500
Larry Garfield <larry@garfieldtech.com> wrote:
abbreviation, etc.) or mutated from one currency (timezone) to another. The currency mutation rules also change rapidly. Neither format nor mutation is reliably related to language or locality.
Sounds like a prime case for a Currency "Value Object" somewhat modeled on the DateTime object (but as a true Value Object, rather than a mutable object). :-)
Pardon my ignorance, do you have the patience to explain? but... you're putting all this responsibility on the site administrator that would specify a string to format it.
Correct, because there is no definitive "Pounds Sterling are always always always displayed in this format" rules. Different clients/use-cases will want it done differently.
In 2 years, I'm not sure if I've ever had 2 clients ask for their dates to be displayed in the same format... and they're all in the Midwestern US! :-) While currency doesn't have as much variation, from earlier on this thread it certainly looks like there's a fair bit.
So, since they will have a "format string" in the admin panel they will format stuff as they wish, even the same format for all the languages. Sure enough you could have in the same site: - float for bathing - float for summer - float for fun - ... but this won't block people from taking advantage of a localised float/currency etc... all over one language section of a web site. 99.9% of sites will need coherent format across a language section and not 99.9% of the web sites will like to have US format as only choice.
No, I'm making a distinction between mutating (which involves exchange rates, which fluctuate hourly) and formatting (which is a string representation of whatever the current decimal is in some format or another). Yes, mutating is probably not a task for
as you said they are orthogonal. The application programmer will provide the "number" as it has to be (already rounded, with the correct exchange ratio bla bla bla), the administrator will provide has it has to be formatted for every language/localisation). The application programmer won't have to code for *every* localisation most of the time... and if it has to... he could.
core. In fact I thing this whole set of functionality belongs in a Money API module of some sort (there's that TLA again! <g>). I am primarily drawing parallels between the complexities of currency and the complexities of time.
Maybe we should express locale in a more complex way: language + "localisation" so that English may be Canadian, UK or US... with some system to avoid content duplication
If I'm a stock broker, then my location/timezone is New York, my language is Spanish (if I'm an immigrant), and I want money displayed in 18 different currencies using international abbreviations (EUR, USD, etc.) Binding the format to a locality or language is going to fail at dozens of edge cases.
The signature of the localisation function take the "symbol" as a parameter. You're providing a way to format the currency, not to compute it. The site will be displayed in Spanish, with Spanish format of currency. If "Spanish" means some of the Latin American countries that may have a different format for currencies... let it be... As since the symbol is passed as a parameter you'll have something like: 1,234.56 EUR 1,234,56 USD or EUR 1.234,56 USD 1.234,56 or 1 234,56 EUR 1 234,56 USD I find it unreasonable to write in the same page: 1,234.56 USD 1 234,56 EUR And in that case you're not dealing with localisation, you're just mixing up everything, you may have your reasons but I'm thinking of a facility that will let module writer "localise" their module if they *can* be localised... if they can't they will deal with it. Anyway the format functions will support a "language" parameter that will override the current user language. At this moment module writer can just display things in US format *or* write their own format functions for the language they are willing to support even if *most* of the time you're just willing to write 1,234.56 EUR vs 1.234,56 EUR
Are you referring to exchange rate? That will be an issue of the application programmer. I'm not interested in an object to store currency... currency will appear magically in a variable (task of the app. programmer)
Variable of what type? With what properties? String or double?
It is up to the application programmer to provide the correct number already rounded. I'd pass integers + the # of decimals.
Who ensures that it's always restricted to two decimal points, and
Passed to the format function. My fault, I put the number of decimal in the wrong place. It shouldn't be in the administrative interface rather in the format function: format_currency($number, $decimal, $symbol, $language=null) I'd limit the scope of this stuff just to *format*. Like PHP number_format but that add symbol and sign position.
based on which rounding scheme (there are several, actually)? There's a lot of logic here that can/should be encapsulated and generalized. That's exactly what Value Objects are good for. (I don't mean object on the level of Node or User or other Assets. I'm talking about more general OO concepts.)
and they have to be formatted accordingly to the locale (maybe a wider concept than what locale is now).
My current locale settings have little bearing on the type of money I am dealing with.
I'd put date/currency/whatever object out of drupal.
Then you're just guessing about how to format float numbers, which is an inherently
I think it's not the task of a CMS to "understand" content unless you're obliged too. So why should you provide a currency object?
... How is it not a CMS's job to understand content? Drupal knows a huge amount about its content right now.
By necessity not by will I hope. The more knowledge you spread in a system the more you make it interdependent and entangled. What I mean is that drupal should know as less as possible about what dates, currency and float are and *why* they have to be formatted in some way (eg. parenthesis vs. sign etc...) this should be up to the site administrator, to provide the right format string and to the application programmer, even rounding is not a task drupal should be aware of, nor exchange rates and timezones; or at least it may provide the information to the application programmer, but it shouldn't know how and why it is used. I'm not proposing a catch them all solution and I think this facility won't get into the way of people. But at this moment every module writer that would like to "localise" float, currency and date format, should read the language variable, write a function that chose a format *for every language he want to support* (not every language the site *actually* support, but really a function aware of every language he want like to support). The net result is: - no one is willing to get into this mess so no module is localised - if any is localised there will be a lot of duplication of code - everyone will provide his own format for float in French so that pages will display float differently accordingly to the module writer idea of what the French format is, if French format is supported at all by the module writer that maybe decided to support just Malay and Bergamasco. - site administrators/builders won't have control on the format Surely a module writer may have HIS reasons to have HIS idea of what is French format and HOW to deal with currencies... but these facilities won't stop him, that is actually dealing with a special case and should be aware of what he is doing, to provide HIS OWN solution to HIS OWN problem. If demand for special format will be high enough you could add: - scientific float - accounting currency - etc... People writing modules will know what will happen to their currency/float if they wrap them with the formatting functions. If they think it doesn't work for them they could avoid it. -- Ivan Sergio Borgonovo http://www.webthatworks.it