Clarifying the Use of `Effect.andThen` to Prevent `Option.none` Issues in TypeScript
question, i recently came across this code of a coworker that he could figure out why it wasn't working (extracted part that is interesting):
This doesn't work, because endThen does a flatMap, so it unwraps the option, and Option.none will throw a NoSuchElement exception.
Replacing the line with Effect.map fixes the issue, but it feels not intuitive for him because the "andThen" should simplify it a lot. According the docs (https://effect.website/docs/guides/essentials/pipeline#andthen):
- a value
- a function returning a value (i.e. same functionality of Effect.map)
- a Promise
- a function returning a Promise
- an Effect
- a function returning an Effect(i.e. same functionality of Effect.flatMap)
Should we improve the docs, to prevent the Option issue, or maybe adapt the andThen?
This doesn't work, because endThen does a flatMap, so it unwraps the option, and Option.none will throw a NoSuchElement exception.
Replacing the line with Effect.map fixes the issue, but it feels not intuitive for him because the "andThen" should simplify it a lot. According the docs (https://effect.website/docs/guides/essentials/pipeline#andthen):
The anotherEffect action can take various forms:
- a value
- a function returning a value (i.e. same functionality of Effect.map)
- a Promise
- a function returning a Promise
- an Effect
- a function returning an Effect(i.e. same functionality of Effect.flatMap)
Should we improve the docs, to prevent the Option issue, or maybe adapt the andThen?
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