What this snippet does
The '!' operator overrides the strict check, promising TypeScript that the property will be initialized externally, bypassing safety.
Expected output
1
Why practise typing this
Typing strict compiler flags 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
- Failing to initialize a class propertyStrict Compiler Flags · intermediate
- Initializing properties via the constructorStrict Compiler Flags · intermediate
- Type-safe usage of callStrict Compiler Flags · intermediate
- Binding a method with correct context and argumentsStrict Compiler Flags · intermediate
- Passing wrong types to call under strict modeStrict Compiler Flags · intermediate
- Declaring an unused variableStrict Compiler Flags · intermediate