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Conditional + annotation causes erroneous typing

microsoft/typescript#39409·111145·Go·2225 天未动·0 条评论·上游最近活跃 ·池内状态:可认领
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<!-- 🚨 STOP 🚨 STOP 🚨 STOP 🚨 Half of all issues filed here are duplicates, answered in the FAQ, or not appropriate for the bug tracker. Even if you think you've found a *bug*, please read the FAQ first, especially the Common "Bugs" That Aren't Bugs section! Please help us by doing the following steps before logging an issue: * Search: https://github.com/Microsoft/TypeScript/search?type=Issues * Read the FAQ: https://github.com/Microsoft/TypeScript/wiki/FAQ Please fill in the *entire* template below. --> <!-- Please try to reproduce the issue with the latest published version. It may have already been fixed. For npm: `typescript@next` This is also the 'Nightly' version in the playground: http://www.typescriptlang.org/play/?ts=Nightly --> **TypeScript Version:** 33.9.4 & 4.0.0@beta <!-- Search terms you tried before logging this (so others can find this issue more easily) --> **Search Terms:** Type annotation wrongly overrides generic with errors **Code** ```ts const createMatrix = <D extends number, T>( dimensions: D, initialValues: T | null = null ): Matrix<D, T> => { const currentDimensionLength = dimensions; const remainingDimensions = dimensions - 1; const needsRecursion = remainingDimensions > 0; const currentMatrix = Array(currentDimensionLength).fill(initialValues); const finalMatrix = needsRecursion ? currentMatrix.map(() => createMatrix(remainingDimensions, initialValues) ) : currentMatrix; return finalMatrix as Matrix<D, T>; }; ``` ```ts type Matrix<D extends number, T> = D extends 1 ? T[] : D extends 2 ? T[][] : D extends 3 ? T[][][] : any[][][][]; ``` **Expected behavior:** Adding type annotations to variables should be compatible with the functions return signature, causing no type errors **Actual behavior:** Assigning an annotated variable to the return value of the function causes an error. The generic `T` is wrongly inferred to be _any of_ `array wh…
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