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tests/cases/conformance/types/typeRelationships/assignmentCompatibility/typeParameterAssignability2.ts(5,5): error TS2322: Type 'T' is not assignable to type 'U'.
'U' could be instantiated with an arbitrary type which could be unrelated to 'T'.
tests/cases/conformance/types/typeRelationships/assignmentCompatibility/typeParameterAssignability2.ts(9,5): error TS2322: Type 'U' is not assignable to type 'T'.
'T' could be instantiated with an arbitrary type which could be unrelated to 'U'.
tests/cases/conformance/types/typeRelationships/assignmentCompatibility/typeParameterAssignability2.ts(14,5): error TS2322: Type 'U' is not assignable to type 'T'.
'T' could be instantiated with an arbitrary type which could be unrelated to 'U'.
tests/cases/conformance/types/typeRelationships/assignmentCompatibility/typeParameterAssignability2.ts(17,5): error TS2322: Type 'V' is not assignable to type 'T'.
'T' could be instantiated with an arbitrary type which could be unrelated to 'V'.
tests/cases/conformance/types/typeRelationships/assignmentCompatibility/typeParameterAssignability2.ts(20,5): error TS2322: Type 'V' is not assignable to type 'U'.
'U' could be instantiated with an arbitrary type which could be unrelated to 'V'.
tests/cases/conformance/types/typeRelationships/assignmentCompatibility/typeParameterAssignability2.ts(25,5): error TS2322: Type 'U' is not assignable to type 'T'.
'U' is assignable to the constraint of type 'T', but 'T' could be instantiated with a different subtype of constraint 'Date'.
tests/cases/conformance/types/typeRelationships/assignmentCompatibility/typeParameterAssignability2.ts(26,5): error TS2322: Type 'V' is not assignable to type 'T'.
'V' is assignable to the constraint of type 'T', but 'T' could be instantiated with a different subtype of constraint 'Date'.
tests/cases/conformance/types/typeRelationships/assignmentCompatibility/typeParameterAssignability2.ts(27,5): error TS2322: Type 'Date' is not assignable to type 'T'.
'Date' is assignable to the constraint of type 'T', but 'T' could be instantiated with a different subtype of constraint 'Date'.
tests/cases/conformance/types/typeRelationships/assignmentCompatibility/typeParameterAssignability2.ts(30,5): error TS2322: Type 'V' is not assignable to type 'U'.
'V' is assignable to the constraint of type 'U', but 'U' could be instantiated with a different subtype of constraint 'Date'.
tests/cases/conformance/types/typeRelationships/assignmentCompatibility/typeParameterAssignability2.ts(31,5): error TS2322: Type 'Date' is not assignable to type 'U'.
'Date' is assignable to the constraint of type 'U', but 'U' could be instantiated with a different subtype of constraint 'Date'.
tests/cases/conformance/types/typeRelationships/assignmentCompatibility/typeParameterAssignability2.ts(35,5): error TS2322: Type 'Date' is not assignable to type 'V'.
'Date' is assignable to the constraint of type 'V', but 'V' could be instantiated with a different subtype of constraint 'Date'.
tests/cases/conformance/types/typeRelationships/assignmentCompatibility/typeParameterAssignability2.ts(45,5): error TS2322: Type 'U' is not assignable to type 'T'.
'U' is assignable to the constraint of type 'T', but 'T' could be instantiated with a different subtype of constraint 'Date'.
tests/cases/conformance/types/typeRelationships/assignmentCompatibility/typeParameterAssignability2.ts(46,5): error TS2322: Type 'V' is not assignable to type 'T'.
'V' is assignable to the constraint of type 'T', but 'T' could be instantiated with a different subtype of constraint 'Date'.
tests/cases/conformance/types/typeRelationships/assignmentCompatibility/typeParameterAssignability2.ts(47,5): error TS2322: Type 'Date' is not assignable to type 'T'.
'Date' is assignable to the constraint of type 'T', but 'T' could be instantiated with a different subtype of constraint 'Date'.
tests/cases/conformance/types/typeRelationships/assignmentCompatibility/typeParameterAssignability2.ts(50,5): error TS2322: Type 'V' is not assignable to type 'U'.
'V' is assignable to the constraint of type 'U', but 'U' could be instantiated with a different subtype of constraint 'Date'.
tests/cases/conformance/types/typeRelationships/assignmentCompatibility/typeParameterAssignability2.ts(51,5): error TS2322: Type 'Date' is not assignable to type 'U'.
'Date' is assignable to the constraint of type 'U', but 'U' could be instantiated with a different subtype of constraint 'Date'.
tests/cases/conformance/types/typeRelationships/assignmentCompatibility/typeParameterAssignability2.ts(55,5): error TS2322: Type 'Date' is not assignable to type 'V'.
'Date' is assignable to the constraint of type 'V', but 'V' could be instantiated with a different subtype of constraint 'Date'.
tests/cases/conformance/types/typeRelationships/assignmentCompatibility/typeParameterAssignability2.ts(64,5): error TS2322: Type 'U' is not assignable to type 'T'.
'T' could be instantiated with an arbitrary type which could be unrelated to 'U'.
tests/cases/conformance/types/typeRelationships/assignmentCompatibility/typeParameterAssignability2.ts(65,5): error TS2322: Type 'V' is not assignable to type 'T'.
'T' could be instantiated with an arbitrary type which could be unrelated to 'V'.
tests/cases/conformance/types/typeRelationships/assignmentCompatibility/typeParameterAssignability2.ts(68,5): error TS2322: Type 'V' is not assignable to type 'U'.
'U' could be instantiated with an arbitrary type which could be unrelated to 'V'.
tests/cases/conformance/types/typeRelationships/assignmentCompatibility/typeParameterAssignability2.ts(70,5): error TS2322: Type 'T' is not assignable to type 'V'.
'V' could be instantiated with an arbitrary type which could be unrelated to 'T'.
tests/cases/conformance/types/typeRelationships/assignmentCompatibility/typeParameterAssignability2.ts(71,5): error TS2322: Type 'U' is not assignable to type 'V'.
'V' could be instantiated with an arbitrary type which could be unrelated to 'U'.
==== tests/cases/conformance/types/typeRelationships/assignmentCompatibility/typeParameterAssignability2.ts (22 errors) ====
// type parameters are not assignable to one another unless directly or indirectly constrained to one another
function foo<T, U extends T>(t: T, u: U) {
t = u; // error
u = t; // ok
~
!!! error TS2322: Type 'T' is not assignable to type 'U'.
!!! error TS2322: 'U' could be instantiated with an arbitrary type which could be unrelated to 'T'.
!!! related TS2208 tests/cases/conformance/types/typeRelationships/assignmentCompatibility/typeParameterAssignability2.ts:3:14: This type parameter might need an `extends U` constraint.
}
function foo2<T extends U, U>(t: T, u: U) {
t = u; // error
~
!!! error TS2322: Type 'U' is not assignable to type 'T'.
!!! error TS2322: 'T' could be instantiated with an arbitrary type which could be unrelated to 'U'.
!!! related TS2208 tests/cases/conformance/types/typeRelationships/assignmentCompatibility/typeParameterAssignability2.ts:8:28: This type parameter might need an `extends T` constraint.
u = t; // ok
}
function foo3<T extends U, U extends V, V>(t: T, u: U, v: V) {
t = u; // error
~
!!! error TS2322: Type 'U' is not assignable to type 'T'.
!!! error TS2322: 'T' could be instantiated with an arbitrary type which could be unrelated to 'U'.
u = t;
t = v; // error
~
!!! error TS2322: Type 'V' is not assignable to type 'T'.
!!! error TS2322: 'T' could be instantiated with an arbitrary type which could be unrelated to 'V'.
!!! related TS2208 tests/cases/conformance/types/typeRelationships/assignmentCompatibility/typeParameterAssignability2.ts:13:41: This type parameter might need an `extends T` constraint.
v = t; // ok
u = v; // error
~
!!! error TS2322: Type 'V' is not assignable to type 'U'.
!!! error TS2322: 'U' could be instantiated with an arbitrary type which could be unrelated to 'V'.
!!! related TS2208 tests/cases/conformance/types/typeRelationships/assignmentCompatibility/typeParameterAssignability2.ts:13:41: This type parameter might need an `extends U` constraint.
v = u; // ok
}
function foo4<T extends U, U extends V, V extends Date>(t: T, u: U, v: V) {
t = u; // error
~
!!! error TS2322: Type 'U' is not assignable to type 'T'.
!!! error TS2322: 'U' is assignable to the constraint of type 'T', but 'T' could be instantiated with a different subtype of constraint 'Date'.
t = v; // error
~
!!! error TS2322: Type 'V' is not assignable to type 'T'.
!!! error TS2322: 'V' is assignable to the constraint of type 'T', but 'T' could be instantiated with a different subtype of constraint 'Date'.
t = new Date(); // error
~
!!! error TS2322: Type 'Date' is not assignable to type 'T'.
!!! error TS2322: 'Date' is assignable to the constraint of type 'T', but 'T' could be instantiated with a different subtype of constraint 'Date'.
u = t;
u = v; // error
~
!!! error TS2322: Type 'V' is not assignable to type 'U'.
!!! error TS2322: 'V' is assignable to the constraint of type 'U', but 'U' could be instantiated with a different subtype of constraint 'Date'.
u = new Date(); // error
~
!!! error TS2322: Type 'Date' is not assignable to type 'U'.
!!! error TS2322: 'Date' is assignable to the constraint of type 'U', but 'U' could be instantiated with a different subtype of constraint 'Date'.
v = t;
v = u;
v = new Date(); // ok
~
!!! error TS2322: Type 'Date' is not assignable to type 'V'.
!!! error TS2322: 'Date' is assignable to the constraint of type 'V', but 'V' could be instantiated with a different subtype of constraint 'Date'.
var d: Date;
d = t; // ok
d = u; // ok
d = v; // ok
}
// same as foo4 with different type parameter ordering
function foo5<V extends Date, U extends V, T extends U>(t: T, u: U, v: V) {
t = u; // error
~
!!! error TS2322: Type 'U' is not assignable to type 'T'.
!!! error TS2322: 'U' is assignable to the constraint of type 'T', but 'T' could be instantiated with a different subtype of constraint 'Date'.
t = v; // error
~
!!! error TS2322: Type 'V' is not assignable to type 'T'.
!!! error TS2322: 'V' is assignable to the constraint of type 'T', but 'T' could be instantiated with a different subtype of constraint 'Date'.
t = new Date(); // error
~
!!! error TS2322: Type 'Date' is not assignable to type 'T'.
!!! error TS2322: 'Date' is assignable to the constraint of type 'T', but 'T' could be instantiated with a different subtype of constraint 'Date'.
u = t;
u = v; // error
~
!!! error TS2322: Type 'V' is not assignable to type 'U'.
!!! error TS2322: 'V' is assignable to the constraint of type 'U', but 'U' could be instantiated with a different subtype of constraint 'Date'.
u = new Date(); // error
~
!!! error TS2322: Type 'Date' is not assignable to type 'U'.
!!! error TS2322: 'Date' is assignable to the constraint of type 'U', but 'U' could be instantiated with a different subtype of constraint 'Date'.
v = t;
v = u;
v = new Date(); // ok
~
!!! error TS2322: Type 'Date' is not assignable to type 'V'.
!!! error TS2322: 'Date' is assignable to the constraint of type 'V', but 'V' could be instantiated with a different subtype of constraint 'Date'.
var d: Date;
d = t; // ok
d = u; // ok
d = v; // ok
}
function foo6<T extends U, U, V>(t: T, u: U, v: V) {
t = u; // error
~
!!! error TS2322: Type 'U' is not assignable to type 'T'.
!!! error TS2322: 'T' could be instantiated with an arbitrary type which could be unrelated to 'U'.
!!! related TS2208 tests/cases/conformance/types/typeRelationships/assignmentCompatibility/typeParameterAssignability2.ts:63:28: This type parameter might need an `extends T` constraint.
t = v; // error
~
!!! error TS2322: Type 'V' is not assignable to type 'T'.
!!! error TS2322: 'T' could be instantiated with an arbitrary type which could be unrelated to 'V'.
!!! related TS2208 tests/cases/conformance/types/typeRelationships/assignmentCompatibility/typeParameterAssignability2.ts:63:31: This type parameter might need an `extends T` constraint.
u = t; // ok
u = v; // error
~
!!! error TS2322: Type 'V' is not assignable to type 'U'.
!!! error TS2322: 'U' could be instantiated with an arbitrary type which could be unrelated to 'V'.
!!! related TS2208 tests/cases/conformance/types/typeRelationships/assignmentCompatibility/typeParameterAssignability2.ts:63:31: This type parameter might need an `extends U` constraint.
v = t; // error
~
!!! error TS2322: Type 'T' is not assignable to type 'V'.
!!! error TS2322: 'V' could be instantiated with an arbitrary type which could be unrelated to 'T'.
v = u; // error
~
!!! error TS2322: Type 'U' is not assignable to type 'V'.
!!! error TS2322: 'V' could be instantiated with an arbitrary type which could be unrelated to 'U'.
!!! related TS2208 tests/cases/conformance/types/typeRelationships/assignmentCompatibility/typeParameterAssignability2.ts:63:28: This type parameter might need an `extends V` constraint.
}
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