Обсуждение: symbol ':'
Where is this symbol used? I see now way to check for correct syntax when ":a" can mean something else that the C variable a. Michael -- Dr. Michael Meskes, Project-Manager | topsystem Systemhaus GmbH meskes@topsystem.de | Europark A2, Adenauerstr. 20 meskes@debian.org | 52146 Wuerselen Go SF49ers! Go Rhein Fire! | Tel: (+49) 2405/4670-44 Use Debian GNU/Linux! | Fax: (+49) 2405/4670-10
> Where is this symbol used? I see now way to check for correct syntax
> when ":a" can mean something else that the C variable a.
It's an allowed operator symbol assigned to a little-used math
operation. You can disallow it for embedded sql if you need to. Another
possibility though is to disallow it as an operator _unless_ it is
inside parentheses. I did a similar thing in gram.y in the BETWEEN/AND
parsing to allow the boolean "AND" operator to be used on the right side
of BETWEEN/AND. But maybe indicator variables are allowed to show up
inside expressions too, so this wouldn't work...
btw, I've been thinking about changing another operator symbol, ";",
because of the obvious parsing ambiguities with the SQL end of statement
symbol. We could change both ":" and ";" operators for v6.4??
- Tom
Thomas G. Lockhart writes: > It's an allowed operator symbol assigned to a little-used math > operation. You can disallow it for embedded sql if you need to. Another Yes, I have to. > possibility though is to disallow it as an operator _unless_ it is > inside parentheses. I did a similar thing in gram.y in the BETWEEN/AND > parsing to allow the boolean "AND" operator to be used on the right side > of BETWEEN/AND. But maybe indicator variables are allowed to show up > inside expressions too, so this wouldn't work... They are. And it's not only indicators. The variables begin with ':', too. > btw, I've been thinking about changing another operator symbol, ";", > because of the obvious parsing ambiguities with the SQL end of statement > symbol. We could change both ":" and ";" operators for v6.4?? Good idea. Michael -- Dr. Michael Meskes, Project-Manager | topsystem Systemhaus GmbH meskes@topsystem.de | Europark A2, Adenauerstr. 20 meskes@debian.org | 52146 Wuerselen Go SF49ers! Go Rhein Fire! | Tel: (+49) 2405/4670-44 Use Debian GNU/Linux! | Fax: (+49) 2405/4670-10