[Scons-users] What to do when scanner is invoked for non-existing file?

[Ilya]

Hello,

SCons manual in "Scanner Objects" section says the following:


> Note that the file is not guaranteed to exist before the scanner is

> called, so the scanner function should check that if there's any

> chance that the scanned file might not exist (for example, if it's

> built from other files).


I have two questions about this:
1. What to do if such condition is detected? Is returning an empty list
sufficient?
2. Is scanner supposed to be called again once file is created?

Ilya