TypeScript

Mutating an object property declared with const in TypeScript

TypeScriptVariables and Declarationslet vs constbeginner

What this snippet does

'const' only prevents reassigning the variable binding, it does not freeze the object properties.

Expected output

Compile Error: Cannot assign to 'obj' because it is a constant.

Why practise typing this

Typing variables and declarations 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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