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[bitemyapp]

From IRC (this was about Cabal, but still holds)

04:25 < Birch> I'm going to be stepping on a plane in a few hours, and would like to get some programming done on the 
               flight. Does anyone have any tips for helping me be productive on the flight? Like making sure my 
               hoogle data is up to date and the like?
04:26 < Birch> Like will I be able to rebuild a sandbox without an internet connection if I once downloaded the 
               dependencies, a la maven?

[snoyberg]

This sounds like a good flag to build and test, perhaps --prefetch, like --dry-run works right now. Should actually be pretty easy to implement.

[snoyberg]

@bitemyapp I just added the --prefetch option, which combined with --dry-run gives the behavior I think you're describing here. Can you give it a shot?

[bitemyapp]

@snoyberg

Edited: needed build in front of the options. There's an opportunity here to avoid confusion I'll elaborate on in another ticket.

[bitemyapp]

@snoyberg it worked for Bloodhound, thank you!