"Given two streams, form a new stream consisting of all entries where, for any given index in the resulting stream, the key of the entry is the element occurring at the same index in the first stream, and the item is the element occurring at the same index in the second stream. The length of the resulting stream is the length of the shorter of the two given streams. Thus: zipEntries(keys,items)[i]==keys[i]->items[i] for every `0<=i<min({keys.size,items.size})`." shared {<Key->Item>*} zipEntries<Key,Item> ({Key*} keys, {Item*} items) given Key satisfies Object given Item satisfies Object => mapPairs(Entry<Key,Item>, keys, items); "Given two streams, form a new stream consisting of all pairs where, for any given index in the resulting stream, the first element of the pair is the element occurring at the same index in the first stream, and the second element of the pair is the element occurring at the same index in the second stream. The length of the resulting stream is the length of the shorter of the two given streams. Thus: zipPairs(xs,ys)[i]==[xs[i],ys[i]] for every `0<=i<min({xs.size,ys.size})`." shared {[First,Second]*} zipPairs<First,Second> ({First*} firstElements, {Second*} secondElements) => mapPairs((First first,Second second) => [first,second], firstElements, secondElements); "Given a stream of values, and a stream of tuples, produce a new stream of tuples formed by prepending the values in the first stream to the tuples in the second stream. The length of the resulting stream is the length of the shorter of the two given streams. Thus: zip(heads, tails)[i]==[heads[i],*tails[i]] for every `0<=i<min({heads.size,tails.size})`." shared {Tuple<Element|Head,Head,Tail>*} zip<Element,Head,Tail> ({Head*} heads, {Tail*} tails) given Tail satisfies Element[] => mapPairs(Tuple<Element|Head,Head,Tail>, heads, tails);