From: leon breedt <bitserf@...>
Date: 2004-10-10T18:35:05+09:00
Subject: DI service change notifications (Syringe)

hi,

i'm playing around with Syringe (http://ruby.jamisbuck.org/syringe/),
and i've got an idea for additional behaviour that i want, though i'm
not sure if its a good idea yet.

what i want, is the option for services to be less static (i.e. not a
singleton  where instantiation happens only once. i want more control
over service lifecycle..)

would what i'm asking for be a different "model", to use Syringe
terminology? the ability to flag a service as dirty, and
automatically, all its consumers get flagged as dirty too, for
refreshing on next usage.

contrived pseudocode example:

env = { :log_filename => 'test.log' }
container.register(:log_filename) { env[:log_filename] }
container.register(:logger) { |c| Logger.new(c.log_filename) }

now, since one can change the value in env, when making that change,
the matching :log_filename service would be flagged as dirty, and, on
next usage, the block executed again, and logger logs to different
file without program restart.

good idea? crap?

leon