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tests/cases/conformance/types/typeRelationships/typeInference/contextualSignatureInstantiation.ts(19,5): error TS2403: Subsequent variable declarations must have the same type. Variable 'b' must be of type 'string | number', but here has type 'unknown'.
tests/cases/conformance/types/typeRelationships/typeInference/contextualSignatureInstantiation.ts(19,13): error TS2345: Argument of type '<T>(x: T, y: T) => T' is not assignable to parameter of type '(x: number, y: string) => number'.
Types of parameters 'y' and 'y' are incompatible.
Type 'string' is not assignable to type 'number'.
tests/cases/conformance/types/typeRelationships/typeInference/contextualSignatureInstantiation.ts(20,5): error TS2403: Subsequent variable declarations must have the same type. Variable 'b' must be of type 'string | number', but here has type 'unknown'.
tests/cases/conformance/types/typeRelationships/typeInference/contextualSignatureInstantiation.ts(20,23): error TS2345: Argument of type '<T>(x: T, y: T) => T' is not assignable to parameter of type '(x: number, y: string) => number'.
Types of parameters 'y' and 'y' are incompatible.
Type 'string' is not assignable to type 'number'.
tests/cases/conformance/types/typeRelationships/typeInference/contextualSignatureInstantiation.ts(21,5): error TS2403: Subsequent variable declarations must have the same type. Variable 'b' must be of type 'string | number', but here has type 'unknown'.
tests/cases/conformance/types/typeRelationships/typeInference/contextualSignatureInstantiation.ts(21,23): error TS2345: Argument of type '<T>(x: T, y: T) => T' is not assignable to parameter of type '(x: string, y: number) => string'.
Types of parameters 'y' and 'y' are incompatible.
Type 'number' is not assignable to type 'string'.
==== tests/cases/conformance/types/typeRelationships/typeInference/contextualSignatureInstantiation.ts (6 errors) ====
// TypeScript Spec, section 4.12.2:
// If e is an expression of a function type that contains exactly one generic call signature and no other members,
// and T is a function type with exactly one non - generic call signature and no other members, then any inferences
// made for type parameters referenced by the parameters of T's call signature are fixed, and e's type is changed
// to a function type with e's call signature instantiated in the context of T's call signature (section 3.8.5).
declare function foo<T>(cb: (x: number, y: string) => T): T;
declare function bar<T, U, V>(x: T, y: U, cb: (x: T, y: U) => V): V;
declare function baz<T, U>(x: T, y: T, cb: (x: T, y: T) => U): U;
declare function g<T>(x: T, y: T): T;
declare function h<T, U>(x: T, y: U): T[] | U[];
var a: number;
var a = bar(1, 1, g); // Should be number
var a = baz(1, 1, g); // Should be number
var b: number | string;
var b = foo(g); // Error, number and string are disjoint types
~
!!! error TS2403: Subsequent variable declarations must have the same type. Variable 'b' must be of type 'string | number', but here has type 'unknown'.
!!! related TS6203 tests/cases/conformance/types/typeRelationships/typeInference/contextualSignatureInstantiation.ts:18:5: 'b' was also declared here.
~
!!! error TS2345: Argument of type '<T>(x: T, y: T) => T' is not assignable to parameter of type '(x: number, y: string) => number'.
!!! error TS2345: Types of parameters 'y' and 'y' are incompatible.
!!! error TS2345: Type 'string' is not assignable to type 'number'.
var b = bar(1, "one", g); // Error, number and string are disjoint types
~
!!! error TS2403: Subsequent variable declarations must have the same type. Variable 'b' must be of type 'string | number', but here has type 'unknown'.
!!! related TS6203 tests/cases/conformance/types/typeRelationships/typeInference/contextualSignatureInstantiation.ts:18:5: 'b' was also declared here.
~
!!! error TS2345: Argument of type '<T>(x: T, y: T) => T' is not assignable to parameter of type '(x: number, y: string) => number'.
!!! error TS2345: Types of parameters 'y' and 'y' are incompatible.
!!! error TS2345: Type 'string' is not assignable to type 'number'.
var b = bar("one", 1, g); // Error, number and string are disjoint types
~
!!! error TS2403: Subsequent variable declarations must have the same type. Variable 'b' must be of type 'string | number', but here has type 'unknown'.
!!! related TS6203 tests/cases/conformance/types/typeRelationships/typeInference/contextualSignatureInstantiation.ts:18:5: 'b' was also declared here.
~
!!! error TS2345: Argument of type '<T>(x: T, y: T) => T' is not assignable to parameter of type '(x: string, y: number) => string'.
!!! error TS2345: Types of parameters 'y' and 'y' are incompatible.
!!! error TS2345: Type 'number' is not assignable to type 'string'.
var b = baz(b, b, g); // Should be number | string
var d: number[] | string[];
var d = foo(h); // Should be number[] | string[]
var d = bar(1, "one", h); // Should be number[] | string[]
var d = bar("one", 1, h); // Should be number[] | string[]
var d = baz(d, d, g); // Should be number[] | string[]
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