Combine two schematics collections

[deanmiller]

Bug Report or Feature Request (mark with an x)

- [ ] bug report -> please search issues before submitting
- [x] feature request

Area

@angular/schematics

Desired functionality

I would like to be able to combine two schematics. Is this possible?

I would like to build some schematics for code generation for my use cases that I plan to apply on top of another schematic. This way I can update each schematics code bases independently.

Example:
ng new --collection=nrwl/schematics+my/schematics

[filipesilva]

See #34 for details about this feature. There's information there about how this can currently be done.