HouYunFei
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29 lines
532 B
Markdown
29 lines
532 B
Markdown
---
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title: Cache Property Access in Loops
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impact: LOW-MEDIUM
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impactDescription: reduces lookups
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tags: javascript, loops, optimization, caching
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---
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## Cache Property Access in Loops
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Cache object property lookups in hot paths.
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**Incorrect (3 lookups × N iterations):**
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```typescript
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for (let i = 0; i < arr.length; i++) {
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process(obj.config.settings.value)
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}
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```
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**Correct (1 lookup total):**
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```typescript
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const value = obj.config.settings.value
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const len = arr.length
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for (let i = 0; i < len; i++) {
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process(value)
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}
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```
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