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Merged
Jake Bailey (jakebailey) merged 1 commit into from
Jun 5, 2024
Merged

for differences between interfaces and type aliases, add note about c… #3087

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1 change: 1 addition & 0 deletions packages/documentation/copy/en/handbook-v2/Everyday Types.md
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Expand Up @@ -469,6 +469,7 @@ You'll learn more about these concepts in later chapters, so don't worry if you
- Type aliases may not participate [in declaration merging, but interfaces can](/play?#code/PTAEEEDtQS0gXApgJwGYEMDGjSfdAIx2UQFoB7AB0UkQBMAoEUfO0Wgd1ADd0AbAK6IAzizp16ALgYM4SNFhwBZdAFtV-UAG8GoPaADmNAcMmhh8ZHAMMAvjLkoM2UCvWad+0ARL0A-GYWVpA29gyY5JAWLJAwGnxmbvGgALzauvpGkCZmAEQAjABMAMwALLkANBl6zABi6DB8okR4Jjg+iPSgABboovDk3jjo5pbW1d6+dGb5djLwAJ7UoABKiJTwjThpnpnGpqPBoTLMAJrkArj4kOTwYmycPOhW6AR8IrDQ8N04wmo4HHQCwYi2Waw2W1S6S8HX8gTGITsQA).
- Interfaces may only be used to [declare the shapes of objects, not rename primitives](/play?#code/PTAEAkFMCdIcgM6gC4HcD2pIA8CGBbABwBtIl0AzUAKBFAFcEBLAOwHMUBPQs0XFgCahWyGBVwBjMrTDJMAshOhMARpD4tQ6FQCtIE5DWoixk9QEEWAeV37kARlABvaqDegAbrmL1IALlAEZGV2agBfampkbgtrWwMAJlAAXmdXdy8ff0Dg1jZwyLoAVWZ2Lh5QVHUJflAlSFxROsY5fFAWAmk6CnRoLGwmILzQQmV8JmQmDzI-SOiKgGV+CaYAL0gBBdyy1KCQ-Pn1AFFplgA5enw1PtSWS+vCsAAVAAtB4QQWOEMKBuYVUiVCYvYQsUTQcRSBDGMGmKSgAAa-VEgiQe2GLgKQA).
- Interface names will [_always_ appear in their original form](/play?#code/PTAEGEHsFsAcEsA2BTATqNrLusgzngIYDm+oA7koqIYuYQJ56gCueyoAUCKAC4AWHAHaFcoSADMaQ0PCG80EwgGNkALk6c5C1EtWgAsqOi1QAb06groEbjWg8vVHOKcAvpokshy3vEgyyMr8kEbQJogAFND2YREAlOaW1soBeJAoAHSIkMTRmbbI8e6aPMiZxJmgACqCGKhY6ABGyDnkFFQ0dIzMbBwCwqIccabcYLyQoKjIEmh8kwN8DLAc5PzwwbLMyAAeK77IACYaQSEjUWY2Q-YAjABMAMwALA+gbsVjNXW8yxySoAADaAA0CCaZbPh1XYqXgOIY0ZgmcK0AA0nyaLFhhGY8F4AHJmEJILCWsgZId4NNfIgGFdcIcUTVfgBlZTOWC8T7kAJ42G4eT+GS42QyRaYbCgXAEEguTzeXyCjDBSAAQSE8Ai0Xsl0K9kcziExDeiQs1lAqSE6SyOTy0AKQ2KHk4p1V6s1OuuoHuzwArMagA) in error messages, but _only_ when they are used by name.
- Using interfaces with `extends` [can often be more performant for the compiler](https://github.com/microsoft/TypeScript/wiki/Performance#preferring-interfaces-over-intersections) than type aliases with intersections

For the most part, you can choose based on personal preference, and TypeScript will tell you if it needs something to be the other kind of declaration. If you would like a heuristic, use `interface` until you need to use features from `type`.

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