34 lines
1.4 KiB
Markdown
34 lines
1.4 KiB
Markdown
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---
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tags:
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- typescript
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---
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# Any
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`any` is a TS-specific type that we can think of it as a higher level parent to
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all the other types that exist in TypeScript.
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It means in effect that either no type declaration has been asserted or that the
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TS compiler cannot infer the type that you mean. Because `any` does not have a
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data type it is equivalent to all the individual scalar and reference types
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combined. In TS this kind of type is called a **supertype**, and specific types
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that actually correspond to a scalar or reference type are known as
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**subtypes**. `any`is the supertype of all types and `string` for example is a
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subtype of `any`.
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> Every value of `string` can be assigned to its supertype`any` but not every
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> value of `any` can be assigned to its subtype `string`
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You can declare `any` as a type if you wish however it is discouraged because it
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effectively undermines the whole purpose of TS. Doing so is basically the same
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thing as declaring a value in normal JS - there is no designation at left hand
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assignation of which type the data belongs to.
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> `any` reflects JavaScript's overarching flexibility; you can see it as a
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> backdoor to a world where you want neither tooling nor type safety.
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`any` means you can escape errors during development. If you are using custom
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types/interfaces and you keep getting an annoying error saying that property X
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doesn't exist on type,, `any` will allow you to overcome it until you go back
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later and refine.
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