TypeScript

Adding a custom Error constructor globally in TypeScript

TypeScriptGlobal Scopedeclare globaladvanced

What this snippet does

Augmenting global interfaces like Window is common in browser environments to inject typed global variables from libraries.

Expected output

defined

Why practise typing this

Typing global scope 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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