Include user interface?

["David A. Wheeler" <dwheeler@dwheeler.com>]

Again, I'm splitting out the email into topics, summarizing, and then 
commenting.

This email is about user interfaces, and whether they should be in scope.

> * Scope: Define this specification as ONLY an interchange format, and at most RECOMMEND user interface issues?

Mecir believes we SHOULD recommend some user interface issues, e.g.,
"operator X can also be presented to the user in the form Y, but must 
always be saved as X - for all cases where it matters."
When I say "UI", I mean "how the formula is perceived by the USER":
do you use commas or semicolons to separate function parameters, and so on.

Mecir says: "the user-perceived format would usually be pretty similar 
to the storage format
- because there's no reason why not."  Agreed.

But Mecir says: "the test-cases show exactly that - user-perceived version."
No, the test cases of OpenFormula show the STORAGE version
(except for XML-quoting special characters like <). For example,
I know of NO spreadsheet implementations where users MUST surround
cell references with [..], but the interchange syntax of OpenFormula
demands it.... and so the test cases do too.


"I would suggest that we say, user-perceived version should look like 
this, unless you have a good reason to differ."
Problem is, everyone has a good reason.  Some implementations, like 
Quattro Pro, actually have skinnable syntaxes -- they vary their display 
syntax, depending on a user setting.  Most implementations' function 
names vary depending on the locale (they translate function names to the 
local language).  Many implementations' decimal point (comma or period) 
also vary depending on the locale.

It would be NIFTY if everyone would agree to a common display format, 
and then made
the storage format identical (or nearly so).  But what's the common format?
Excel, Gnumeric, SheetToGo all use "," for function parameters, which is 
horrific
if you want to support locales where "," is the decimal separator.
They also use "," for the "union" operator (how silly!).
Is ".." or ":" the range operator? Is "=" or "==" equal-to?
And if cell references aren't surrounded by [..], there are nasty 
ambiguity problems
that are no problem for human-written text, but as a storage format it's 
terrible.

We could devise a RECOMMENDED user interface format; that'd be great.
There might still be occasional variance between that and
the storage format (e.g., [..] as a cell reference marker).
Otherwise, is QT3 a variable, or a cell in a spreadsheet with lots of 
columns?
But I'd hate to MANDATE that.


--- David A. Wheeler