43 lines
1.6 KiB
Markdown
43 lines
1.6 KiB
Markdown
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up:: [[TypeScript]]
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# Typscript (not)to annotate all types
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explicit manifest type annotations can be thought of as *double-entry bookkeeping* in accounting: when you do everything right, it should never be needed. - **some say**
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A good rule of thumb is:
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> Every public interface should be explicitly annotated, unless the type is blindingly obvious both from the name and the implementation
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>
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So, for something like
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```tsx
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export const toString = (num) => `${num}`
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```
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Some believe its ok to leave out type annotations - even tho num would normally be typed - just example
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I’ve come to find out that its 100% preference.
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Some believe you write cleaner code by letting typescript infer the return types. Some believe its cleaner and more readable **without** inferring
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I personally am a huge fan of typing everything. So for me, this feels much much better:
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```tsx
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export const toString = (num: number): string => `${num}`
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```
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I just FEEL better.
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Whether its cleaner to someone else or not, or pointless for me to do. Its 100% preference and this is my preference.
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Obviously when working on a team, you want to write code that appeals to the team and not just yourself.
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But you’ll never satisfy anyone with your personal taste because everyone has a different taste.
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The closer mistake to the type declaration: the easier it is to fix it. If you, after refactoring, accidentally change the `return` expression so that it returns a different type - the type check error
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will be triggered several layers deeper on the first caller whose
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expectations you have broken (if any).
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*always type all functions explicitly. - **my motto***
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