What this snippet does
The satisfies operator ensures an expression matches a type without changing the inferred type of the expression.
Expected output
1
Why practise typing this
Typing modern typescript 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
- Type-safe theme configuration with satisfiesModern TypeScript · intermediate
- Losing literal types by annotating instead of satisfiesModern TypeScript · intermediate
- Declaring variables with primitive typesBasic Types · beginner
- Typing function parameters with primitivesBasic Types · beginner
- Assigning a string to a number variableBasic Types · beginner
- Defining an array of numbersBasic Types · beginner