New v2.1 arktype matcher: is there a way to match on string literal values?
An example from the docs:
If I try to switch this to a typical string-value based discriminated union, I get an error:
'one is unresolvable' and 'two is unresolvable'
type Data =
| {
id: 1
oneValue: number
}
| {
id: 2
twoValue: string
}
const discriminateValue = match
// .in allows you to specify the input TypeScript allows for your matcher
.in<Data>()
// .at allows you to specify a key at which your input will be matched
.at("id")
.match({
1: o => `${o.oneValue}!`,
2: o => o.twoValue.length,
default: "assert"
})type Data =
| {
id: 1
oneValue: number
}
| {
id: 2
twoValue: string
}
const discriminateValue = match
// .in allows you to specify the input TypeScript allows for your matcher
.in<Data>()
// .at allows you to specify a key at which your input will be matched
.at("id")
.match({
1: o => `${o.oneValue}!`,
2: o => o.twoValue.length,
default: "assert"
})If I try to switch this to a typical string-value based discriminated union, I get an error:
type Data =
| {
id: "one";
oneValue: number;
}
| {
id: "two";
twoValue: string;
};
const discriminateValue = match
// .in allows you to specify the input TypeScript allows for your matcher
.in<Data>()
// .at allows you to specify a key at which your input will be matched
.at("id")
.match({
one: (o) => `${o.oneValue}!`,
two: (o) => o.twoValue.length,
default: "assert",
});type Data =
| {
id: "one";
oneValue: number;
}
| {
id: "two";
twoValue: string;
};
const discriminateValue = match
// .in allows you to specify the input TypeScript allows for your matcher
.in<Data>()
// .at allows you to specify a key at which your input will be matched
.at("id")
.match({
one: (o) => `${o.oneValue}!`,
two: (o) => o.twoValue.length,
default: "assert",
});'one is unresolvable' and 'two is unresolvable'
