type-narrowing
CommunitySafely refine types with conditional checks.
Software Engineering#typescript#discriminated-unions#control-flow#type-guards#type-narrowing#runtime-safety#null-check
Authorluyi985
Version1.0.0
Installs0
System Documentation
What problem does it solve?
Type narrowing helps TypeScript refine broad union and nullable types based on control flow, reducing unnecessary type assertions and preventing runtime errors.
Core Features & Use Cases
- Null/undefined checks to narrow types
- typeof and instanceof guards to discriminate between alternatives
- Discriminated unions (tagged unions) via kind to narrow to a specific variant
- Using in operator for property presence checks
- Throw/Return early patterns to guarantee narrowed types after guard
- User-defined type guards to extend narrowing
Quick Start
Apply type-narrowing in a function that handles union or nullable values to let TypeScript infer the precise type
Dependency Matrix
Required Modules
None requiredComponents
Standard package💻 Claude Code Installation
Recommended: Let Claude install automatically. Simply copy and paste the text below to Claude Code.
Please help me install this Skill: Name: type-narrowing Download link: https://github.com/luyi985/lyi-bash/archive/main.zip#type-narrowing Please download this .zip file, extract it, and install it in the .claude/skills/ directory.
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