- From: Bjoern Hoehrmann <derhoermi@gmx.net>
- Date: Wed, 08 Sep 2010 03:39:38 +0200
- To: Håkon Wium Lie <howcome@opera.com>
- Cc: www-style@w3.org, www-svg@w3.org
* Håkon Wium Lie wrote: >Introducing e-notation in CSS would have a considerable cost. We would >need to change the CSS core grammar, which is -- sort of -- our >constitution. Constitutions can be changed, but only for truly >important things, when there is long-standing consensus. The CSS Working Group changes the core syntax on average anually, and allowing this notation would not require changes to the core syntax: <number> [eE] - <integer> <unit>? is tokenized as DIMENSION, <number> [eE] + <integer> is tokenized as DIMENSION DELIM NUMBER, and <number> [eE] + <integer> <unit> is tokenized as DIMENSION DELIM DIMENSION (and all these sequences are allowed in the relevant places). It may be beneficial to change the core rules (giving scientific numbers and scientific dimensions their own tokens so comments between the tokens are disallowed and to disallow non-integer exponents) and there would be a difference between SVG and CSS in that CSS would likely allow the "e" and the unit identifier to be escaped, but these are all familiar issues. Having scientific notation in CSS or SVG is not really useful, the numbers where some may consider them beneficial will typically be beyond specification or implementation limits or be unstable, e.g. due to accumulated rounding errors; SVG Tiny 1.2 for instance has the bounds -32,767.9999 to +32,767.9999 (with at most that many digits). It's at best useful for content that won't work very well. -- Björn Höhrmann · mailto:bjoern@hoehrmann.de · http://bjoern.hoehrmann.de Am Badedeich 7 · Telefon: +49(0)160/4415681 · http://www.bjoernsworld.de 25899 Dagebüll · PGP Pub. KeyID: 0xA4357E78 · http://www.websitedev.de/
Received on Wednesday, 8 September 2010 01:40:16 UTC