Here's what I want to do: I have a large header photo for the home page (that works)
Then, I want some pages to have a different header photo (services, about us and team)
I also want a fall-back photo for all the other pages (hence the final else statement)
Background on this: Template code parsing is done in sapphire/core/SSViewer.php. The function parseTemplateContent runs template code through a series of regular expressions which replace template code constructs with PHP code. These regular expressions support an arbitrary combination of call signatures. The call you are trying to make isnâ€™t one of the supported call syntaxes.
A [url=http://open.silverstripe.org/ticket/3738]patch[/url] has been submitted for testing which would remove these arbitrary constraints. So, code like <% else_if Call1(Arg1) %> should work. Would you have time to help test this patch?