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=== tests/cases/compiler/chainedCallsWithTypeParameterConstrainedToOtherTypeParameter2.ts ===
class Chain<T> {
>Chain : Chain<T>
constructor(public value: T) { }
>value : T
then<S extends T>(cb: (x: T) => S): Chain<S> {
>then : <S extends T>(cb: (x: T) => S) => Chain<S>
>cb : (x: T) => S
>x : T
var t: T;
>t : T
var s: S;
>s : S
// Ok to go down the chain, but error to climb up the chain
(new Chain(t)).then(tt => s).then(ss => t);
>(new Chain(t)).then(tt => s).then(ss => t) : Chain<S>
>(new Chain(t)).then(tt => s).then : <S extends S>(cb: (x: S) => S) => Chain<S>
>(new Chain(t)).then(tt => s) : Chain<S>
>(new Chain(t)).then : <S extends T>(cb: (x: T) => S) => Chain<S>
>(new Chain(t)) : Chain<T>
>new Chain(t) : Chain<T>
>Chain : typeof Chain
>t : T
>then : <S extends T>(cb: (x: T) => S) => Chain<S>
>tt => s : (tt: T) => S
>tt : T
>s : S
>then : <S extends S>(cb: (x: S) => S) => Chain<S>
>ss => t : (ss: S) => T
>ss : S
>t : T
// But error to try to climb up the chain
(new Chain(s)).then(ss => t);
>(new Chain(s)).then(ss => t) : Chain<S>
>(new Chain(s)).then : <S extends S>(cb: (x: S) => S) => Chain<S>
>(new Chain(s)) : Chain<S>
>new Chain(s) : Chain<S>
>Chain : typeof Chain
>s : S
>then : <S extends S>(cb: (x: S) => S) => Chain<S>
>ss => t : (ss: S) => T
>ss : S
>t : T
// Staying at T or S should be fine
(new Chain(t)).then(tt => t).then(tt => t).then(tt => t);
>(new Chain(t)).then(tt => t).then(tt => t).then(tt => t) : Chain<T>
>(new Chain(t)).then(tt => t).then(tt => t).then : <S extends T>(cb: (x: T) => S) => Chain<S>
>(new Chain(t)).then(tt => t).then(tt => t) : Chain<T>
>(new Chain(t)).then(tt => t).then : <S extends T>(cb: (x: T) => S) => Chain<S>
>(new Chain(t)).then(tt => t) : Chain<T>
>(new Chain(t)).then : <S extends T>(cb: (x: T) => S) => Chain<S>
>(new Chain(t)) : Chain<T>
>new Chain(t) : Chain<T>
>Chain : typeof Chain
>t : T
>then : <S extends T>(cb: (x: T) => S) => Chain<S>
>tt => t : (tt: T) => T
>tt : T
>t : T
>then : <S extends T>(cb: (x: T) => S) => Chain<S>
>tt => t : (tt: T) => T
>tt : T
>t : T
>then : <S extends T>(cb: (x: T) => S) => Chain<S>
>tt => t : (tt: T) => T
>tt : T
>t : T
(new Chain(s)).then(ss => s).then(ss => s).then(ss => s);
>(new Chain(s)).then(ss => s).then(ss => s).then(ss => s) : Chain<S>
>(new Chain(s)).then(ss => s).then(ss => s).then : <S extends S>(cb: (x: S) => S) => Chain<S>
>(new Chain(s)).then(ss => s).then(ss => s) : Chain<S>
>(new Chain(s)).then(ss => s).then : <S extends S>(cb: (x: S) => S) => Chain<S>
>(new Chain(s)).then(ss => s) : Chain<S>
>(new Chain(s)).then : <S extends S>(cb: (x: S) => S) => Chain<S>
>(new Chain(s)) : Chain<S>
>new Chain(s) : Chain<S>
>Chain : typeof Chain
>s : S
>then : <S extends S>(cb: (x: S) => S) => Chain<S>
>ss => s : (ss: S) => S
>ss : S
>s : S
>then : <S extends S>(cb: (x: S) => S) => Chain<S>
>ss => s : (ss: S) => S
>ss : S
>s : S
>then : <S extends S>(cb: (x: S) => S) => Chain<S>
>ss => s : (ss: S) => S
>ss : S
>s : S
return null;
>null : null
}
}
// Similar to above, but T is now constrained. Verify that the constraint is maintained across invocations
interface I {
x: number;
>x : number
}
class Chain2<T extends I> {
>Chain2 : Chain2<T>
constructor(public value: T) { }
>value : T
then<S extends T>(cb: (x: T) => S): Chain2<S> {
>then : <S extends T>(cb: (x: T) => S) => Chain2<S>
>cb : (x: T) => S
>x : T
var i: I;
>i : I
var t: T;
>t : T
var s: S;
>s : S
// Ok to go down the chain, check the constraint at the end.
// Should get an error that we are assigning a string to a number
(new Chain2(i)).then(ii => t).then(tt => s).value.x = "";
>(new Chain2(i)).then(ii => t).then(tt => s).value.x = "" : ""
>(new Chain2(i)).then(ii => t).then(tt => s).value.x : number
>(new Chain2(i)).then(ii => t).then(tt => s).value : S
>(new Chain2(i)).then(ii => t).then(tt => s) : Chain2<S>
>(new Chain2(i)).then(ii => t).then : <S extends T>(cb: (x: T) => S) => Chain2<S>
>(new Chain2(i)).then(ii => t) : Chain2<T>
>(new Chain2(i)).then : <S extends I>(cb: (x: I) => S) => Chain2<S>
>(new Chain2(i)) : Chain2<I>
>new Chain2(i) : Chain2<I>
>Chain2 : typeof Chain2
>i : I
>then : <S extends I>(cb: (x: I) => S) => Chain2<S>
>ii => t : (ii: I) => T
>ii : I
>t : T
>then : <S extends T>(cb: (x: T) => S) => Chain2<S>
>tt => s : (tt: T) => S
>tt : T
>s : S
>value : S
>x : number
>"" : ""
// Staying at T or S should keep the constraint.
// Get an error when we assign a string to a number in both cases
(new Chain2(i)).then(ii => t).then(tt => t).then(tt => t).then(tt => t).value.x = "";
>(new Chain2(i)).then(ii => t).then(tt => t).then(tt => t).then(tt => t).value.x = "" : ""
>(new Chain2(i)).then(ii => t).then(tt => t).then(tt => t).then(tt => t).value.x : number
>(new Chain2(i)).then(ii => t).then(tt => t).then(tt => t).then(tt => t).value : T
>(new Chain2(i)).then(ii => t).then(tt => t).then(tt => t).then(tt => t) : Chain2<T>
>(new Chain2(i)).then(ii => t).then(tt => t).then(tt => t).then : <S extends T>(cb: (x: T) => S) => Chain2<S>
>(new Chain2(i)).then(ii => t).then(tt => t).then(tt => t) : Chain2<T>
>(new Chain2(i)).then(ii => t).then(tt => t).then : <S extends T>(cb: (x: T) => S) => Chain2<S>
>(new Chain2(i)).then(ii => t).then(tt => t) : Chain2<T>
>(new Chain2(i)).then(ii => t).then : <S extends T>(cb: (x: T) => S) => Chain2<S>
>(new Chain2(i)).then(ii => t) : Chain2<T>
>(new Chain2(i)).then : <S extends I>(cb: (x: I) => S) => Chain2<S>
>(new Chain2(i)) : Chain2<I>
>new Chain2(i) : Chain2<I>
>Chain2 : typeof Chain2
>i : I
>then : <S extends I>(cb: (x: I) => S) => Chain2<S>
>ii => t : (ii: I) => T
>ii : I
>t : T
>then : <S extends T>(cb: (x: T) => S) => Chain2<S>
>tt => t : (tt: T) => T
>tt : T
>t : T
>then : <S extends T>(cb: (x: T) => S) => Chain2<S>
>tt => t : (tt: T) => T
>tt : T
>t : T
>then : <S extends T>(cb: (x: T) => S) => Chain2<S>
>tt => t : (tt: T) => T
>tt : T
>t : T
>value : T
>x : number
>"" : ""
(new Chain2(i)).then(ii => s).then(ss => s).then(ss => s).then(ss => s).value.x = "";
>(new Chain2(i)).then(ii => s).then(ss => s).then(ss => s).then(ss => s).value.x = "" : ""
>(new Chain2(i)).then(ii => s).then(ss => s).then(ss => s).then(ss => s).value.x : number
>(new Chain2(i)).then(ii => s).then(ss => s).then(ss => s).then(ss => s).value : S
>(new Chain2(i)).then(ii => s).then(ss => s).then(ss => s).then(ss => s) : Chain2<S>
>(new Chain2(i)).then(ii => s).then(ss => s).then(ss => s).then : <S extends S>(cb: (x: S) => S) => Chain2<S>
>(new Chain2(i)).then(ii => s).then(ss => s).then(ss => s) : Chain2<S>
>(new Chain2(i)).then(ii => s).then(ss => s).then : <S extends S>(cb: (x: S) => S) => Chain2<S>
>(new Chain2(i)).then(ii => s).then(ss => s) : Chain2<S>
>(new Chain2(i)).then(ii => s).then : <S extends S>(cb: (x: S) => S) => Chain2<S>
>(new Chain2(i)).then(ii => s) : Chain2<S>
>(new Chain2(i)).then : <S extends I>(cb: (x: I) => S) => Chain2<S>
>(new Chain2(i)) : Chain2<I>
>new Chain2(i) : Chain2<I>
>Chain2 : typeof Chain2
>i : I
>then : <S extends I>(cb: (x: I) => S) => Chain2<S>
>ii => s : (ii: I) => S
>ii : I
>s : S
>then : <S extends S>(cb: (x: S) => S) => Chain2<S>
>ss => s : (ss: S) => S
>ss : S
>s : S
>then : <S extends S>(cb: (x: S) => S) => Chain2<S>
>ss => s : (ss: S) => S
>ss : S
>s : S
>then : <S extends S>(cb: (x: S) => S) => Chain2<S>
>ss => s : (ss: S) => S
>ss : S
>s : S
>value : S
>x : number
>"" : ""
return null;
>null : null
}
}
|
