how to combine AstNodeDescription into Stream<AstNodeDescription>

[zrwsmd]

 const ss = stream(allMembers)
      .map((e) => {
        //nextVariables string[]
        let nextVariables = e.nextVariables;
        if (nextVariables.length > 0) {
          for (let i = 0; i < nextVariables.length; i++) {
            const nextVariable = nextVariables[i];
            //let astNodeDescription: AstNodeDescription =this.descriptions.createDescription(e, nextVariable);
            return this.descriptions.createDescription(e, nextVariable);
          }
        }
      }) .nonNullable();
	  let s2 = new StreamScope(ss);

if i write like this,it can only return first element astNodeDescription info of nextVariables array,
actually i want to combine all astNodeDescription info of nextVariables array,how to modify it

[msujew]

Hey @zrwsmd,

everything you would need to do is not return a single description in the map call, but an array that you then flatten (or just call flatMap directly):

 const ss = allMembers
      .flatMap((e) => {
        const descriptions = [];
        let nextVariables = e.nextVariables;
        for (let i = 0; i < nextVariables.length; i++) {
          const nextVariable = nextVariables[i];
          descriptions.push(this.descriptions.createDescription(e, nextVariable));
        }
        return descriptions;
      });
  let s2 = new StreamScope(stream(ss));

[spoenemann]

To enable lazy evaluation, I'd use flatMap on a Stream:

const ss = stream(allMembers)
      .flatMap((e) => stream(e.nextVariables)
            .map(nextVariable => this.descriptions.createDescription(e, nextVariable))
      );
let s2 = new StreamScope(ss);