Aborting Early

Sometimes a single field has multiple checks. A password field, for example, might first check that it is not empty, and then check that it is at least 8 characters long. If the password is empty, there is no point telling the user it must be at least 8 characters. They haven’t provided a password at all. The only error that matters is: “password is required.”

.abort() solves this. You call it on a check, and if that check fails, Schema stops running any further checks on that same value, even when { errors: "all" } is active.

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import { Schema } from "effect";
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const User = Schema.Struct({
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  email: Schema.String,
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  password: Schema.String.check(
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    Schema.isMinLength(1).abort(), // If empty, stop here
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    Schema.isMinLength(8), // Must be at least 8 characters
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    Schema.isPattern(/\d/), // Must contain at least one digit
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  ),
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});
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const result = Schema.decodeUnknownExit(User)(
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  { email: "alice@example.com", password: "" },
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  { errors: "all" },
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);
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console.log(String(result));

Output:

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Failure(Cause([Fail(SchemaError(Expected a value with a length of at least 1, got ""
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  at ["password"]))]))

The password "hi" is only 2 characters, so it fails the isMinLength(8) check. Because that check has .abort(), Schema does not bother checking whether the password contains a digit. Only the length error is reported.