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{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Wrong type inferred for indirect call of generic function ","articleBody":"**TypeScript Version:** 3.2.2\r\n\r\n**Search Terms:** Generics, lookahead, type inference\r\n\r\n**Code**\r\n\r\n```ts\r\nfunction call\u003cP1, R\u003e(f: (p1: P1) =\u003e R, p1: P1): R {\r\n    return f(p1);\r\n}\r\n\r\nfunction identity\u003cT\u003e(o: T): T {\r\n    return o;\r\n}\r\n\r\nconst x = call(identity, 1);\r\n\r\n\r\n// When the parameters are reversed, it works:\r\n\r\nfunction callReversed\u003cP1, R\u003e(p1: P1, f: (p1: P1) =\u003e R): R {\r\n    return f(p1);\r\n}\r\n\r\nconst y = callReversed(1, identity);\r\n```\r\n\r\n\r\n\r\n**Expected behavior:**\r\n\r\n`x` is of type `number`\r\n\r\n**Actual behavior:**\r\n\r\n`x` is of type `{}`\r\nonly `y` is of type number\r\n\r\n**Playground Link:** [Playground link](https://www.typescriptlang.org/play/#src=function%20call%3CP1%2C%20R%3E(f%3A%20(p1%3A%20P1)%20%3D%3E%20R%2C%20p1%3A%20P1)%3A%20R%20%7B%0A%20%20%20%20return%20f(p1)%3B%0A%7D%0A%0Afunction%20identity%3CT%3E(o%3A%20T)%3A%20T%20%7B%0A%20%20%20%20return%20o%3B%0A%7D%0A%0Aconst%20x%20%3D%20call(identity%2C%201)%3B%0A%0A%0A%2F%2F%20Reversed%3A%0A%0Afunction%20callReversed%3CP1%2C%20R%3E(p1%3A%20P1%2C%20f%3A%20(p1%3A%20P1)%20%3D%3E%20R)%3A%20R%20%7B%0A%20%20%20%20return%20f(p1)%3B%0A%7D%0A%0Aconst%20y%20%3D%20callReversed(1%2C%20identity)%3B%0A)\r\n\r\n**Related Issues:** I didn't find anything related, but maybe I have been using the wrong search term (\"lookahead\").\r\n","author":{"url":"https://github.com/tp","@type":"Person","name":"tp"},"datePublished":"2019-01-29T18:47:30.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":5},"url":"https://github.com/29638/TypeScript/issues/29638"}