Format: YYYY-MM-DD-description.md - 2026-01-19-infrastructure-deployment.md - 2026-01-19-backend-api-implementation.md (in progress) Co-Authored-By: Claude Sonnet 4.5 (1M context) <noreply@anthropic.com>
41 lines
980 B
Markdown
41 lines
980 B
Markdown
---
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title: Use Explicit Conditional Rendering
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impact: LOW
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impactDescription: prevents rendering 0 or NaN
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tags: rendering, conditional, jsx, falsy-values
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---
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## Use Explicit Conditional Rendering
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Use explicit ternary operators (`? :`) instead of `&&` for conditional rendering when the condition can be `0`, `NaN`, or other falsy values that render.
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**Incorrect (renders "0" when count is 0):**
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```tsx
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function Badge({ count }: { count: number }) {
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return (
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<div>
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{count && <span className="badge">{count}</span>}
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</div>
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)
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}
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// When count = 0, renders: <div>0</div>
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// When count = 5, renders: <div><span class="badge">5</span></div>
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```
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**Correct (renders nothing when count is 0):**
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```tsx
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function Badge({ count }: { count: number }) {
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return (
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<div>
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{count > 0 ? <span className="badge">{count}</span> : null}
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</div>
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)
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}
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// When count = 0, renders: <div></div>
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// When count = 5, renders: <div><span class="badge">5</span></div>
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```
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