1️⃣
✅ string + string | number => string
❌ number + string | number => error 2365

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2️⃣
❌ No error firing on generic wrong return type.

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3️⃣
❌ Type guard wrong types intersection via casting to unknown.

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4️⃣
🤔 Guarded type narrowing.

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5️⃣
🧐 A bit more complex guarded type.

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6️⃣
❌ Inaccurate "1/1" | "2/2" type inference.

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7️⃣
❌ No errors when mutating tuples by number index.

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8️⃣
❌ Interface doesn't fit Record<string, unknown>.

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9️⃣
🤯 Type any passes extends operator along both branches.

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🔟
❌ Brand as key of Record might be type unsafe.
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🤨 But Flavour as key of Record is just OK.
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1️⃣1️⃣
😢 Would be more useful to warn about useless operations.

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1️⃣2️⃣
❌ No error on Record<string, number> addition assignments with
"compilerOptions": {
"noUncheckedIndexedAccess": true
}

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