TypeScript

Failing to pass extra config to a function in TypeScript

TypeScriptObjects and InterfacesExcess Property Checksbeginner

What this snippet does

Excess property checking catches typos and invalid properties when passing literals directly to functions.

Expected output

Compile Error: Object literal may only specify known properties, and 'timeout' does not exist in type 'ServerConfig'.

Why practise typing this

Typing objects and interfaces 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.

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