20 lines
541 B
Markdown
20 lines
541 B
Markdown
The short answer is: **no, they are not equal**:
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The difference is that if an error happens in `f1`, then it is handled by `.catch` here:
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```js run
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promise
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.then(f1)
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.catch(f2);
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```
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...But not here:
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```js run
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promise
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.then(f1, f2);
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```
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That's because an error is passed down the chain, and in the second code piece there's no chain below `f1`.
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In other words, `.then` passes results/errors to the next `.then/catch`. So in the first example, there's a `catch` below, and in the second one there isn't, so the error is unhandled.
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