flyd-zip v0.0.1

Creates a stream with values from streams lined up with each other. For example if you have two streams with values 1, 2, 3 and 4, 5, 6, 7, the result stream will emit 1, 4, 2, 5, and 3, 6. The result stream will emit the next value only when it has at least one value from each source.

const s1 = flyd.stream()
const s2 = flyd.stream()
const zipped = zip([s1, s2])
s1(1)
s2(2)
zipped() // [1, 2]
s2(3)
zipped() // [1, 2] -- s1 still has old value so zipped does not change
s1(4)
zipped() // [4, 3]

Zip is not like lift, because lift will give you a pair for every new value:

const s1 = flyd.stream()
const s2 = flyd.stream()
const lifted = lift((v1, v2) => [v1, v2], s1, s2)

s1(1)
s2(2)
lifted() // [1,2]
s2(3)    // [1,3]

Lift will give you a pair for any new value on any new stream. Instead, zip gives you only pairs of new values, where both values have to be new to produce a new pair on the zipped stream.