Passing subproject-specific config options in craft blueprints. A little help?

Can someone point me to a syntax, example or documentation for implementing conditional config options in a blueprint in craft to pass through to a sub-project?

I’m working on a blueprint that needs to pass ‘-D use-network=true’ to a subproject in the event that subproject is triggered and builds.

I’m assuming there’s some if self.subinfo.somethingorother path I can follow but I’m not finding any comprehensive documentation, and reading through the craft source is taking a bit, with some possibles, but a little pointer would be much appreciated.

[To be clear, my issue was meson-specific. YMMV for other build systems.]

For anyone facing the same question, I found the answer in the Meson docs here:

Specifically, using the subproject I needed to address, I used this syntax. Note the subproject name prepended with a colon separator:

self.subinfo.options.configure.args += ["-Dmm-common:use-network=true"]