javascript - Empty set in type script -


i have theoretical question. there way design type in typescript denotes empty set? tried define 1 using union, disjoint union, intersection , more...

yes, although think usefulness of such type depends lot on style of programming. define emptyset this:

interface iset {      intersection: (s: iset) => iset;     union: (s: iset) => iset; }  class emptyset implements iset {      intersection(s: iset) {          return this;     }      union(s: iset) {          return s;     } }  class nonemptyset implements iset { ... }

iset generic contract of set, emptyset concrete type implements contract. can more things set union , intersection, example.


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