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tests/cases/conformance/types/typeRelationships/assignmentCompatibility/genericCallWithObjectTypeArgsAndInitializers.ts(5,33): error TS2322: Type 'number' is not assignable to type 'T'.
'number' is assignable to the constraint of type 'T', but 'T' could be instantiated with a different subtype of constraint 'Number'.
tests/cases/conformance/types/typeRelationships/assignmentCompatibility/genericCallWithObjectTypeArgsAndInitializers.ts(6,37): 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/genericCallWithObjectTypeArgsAndInitializers.ts(8,56): 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/genericCallWithObjectTypeArgsAndInitializers.ts (3 errors) ====
// Generic typed parameters with initializers
function foo<T>(x: T = null) { return x; } // ok
function foo2<T>(x: T = undefined) { return x; } // ok
function foo3<T extends Number>(x: T = 1) { } // error
~~~~~~~~
!!! error TS2322: Type 'number' is not assignable to type 'T'.
!!! error TS2322: 'number' is assignable to the constraint of type 'T', but 'T' could be instantiated with a different subtype of constraint 'Number'.
function foo4<T, U extends T>(x: T, y: U = x) { } // error
~~~~~~~~
!!! 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/genericCallWithObjectTypeArgsAndInitializers.ts:6:15: This type parameter might need an `extends U` constraint.
function foo5<T, U extends T>(x: U, y: T = x) { } // ok
function foo6<T, U extends T, V extends U>(x: T, y: U, z: V = y) { } // 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'.
function foo7<T, U extends T, V extends U>(x: V, y: U = x) { } // should be ok
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