What this snippet does
When fed a union, conditional types distribute over the union, resulting in an array for each type, not a single array of the union.
Expected output
check type
Why practise typing this
Typing conditional types code builds muscle memory for the symbols and indentation TypeScript uses most, which prose-based typing tests never cover. DevType measures your words per minute and accuracy on this snippet and tracks the individual characters you mistype, so later lessons can target them.
More TypeScript practice
- Basic ternary type logicConditional Types · intermediate
- Inferring response type based on inputConditional Types · intermediate
- Inferring the element type of an arrayConditional Types · intermediate
- Extracting the resolved type of a PromiseConditional Types · intermediate
- Inferring from a non-matching typeConditional Types · intermediate
- Filtering types out of a unionConditional Types · intermediate