So Pants is made up with a network of rules. Those rules are 'run' when we call

Get(Result, Request, data)

Pants assumes that

data

is immutable, and forces

data

to be hashable. This then allows Pants to memoise/cache calls to

Get

so no matter how many times

Get(Result, Request, 1)

is called, the rule will only ever get executed once. Oh and everything is async. How does Pants handle

MultiGet( Get(Result, Request, 1), Get(Result, Request 1) )

? Is this undefined behaviour? or can we still trust that the rule will only be ran once?

Still only run once 🙂 It happens pretty frequently that multiple rules need the same thing at the same time, like downloading PEX

sweet

Btw that deduplication happens regardless of Pantsd -- the difference with Pantsd is we preserve the memoization across "sessions" (

./pants

invokes)

neato