Implementstypia.functional.match for compile-time pattern matching on union types, addressing issue#1348. This feature generates optimized conditional statements at compile-time, similar to ts-pattern but leveraging typia's transformation capabilities.

Key Features

• Compile-time transformation: Converts pattern matching expressions into optimized if-else chains
• Union type analysis: Uses typia's MetadataFactory to analyze TypeScript union types
• Type-safe matching: Maintains full TypeScript type safety throughout the matching process
• Error handling: Supports optionalotherwise handler for unmatched cases

API Usage

typeAnimal=|{type:'dog';breed:string;}|{type:'cat';lives:number;}|{type:'bird';canFly:boolean;};constresult=typia.functional.match(animal,{dog:(dog)=>`Dog of breed:${dog.breed}`,cat:(cat)=>`Cat with${cat.lives} lives`,bird:(bird)=>`Bird that${bird.canFly ?'can' :'cannot'} fly`,},(error)=>`No match found`);

This will be transformed at compile-time into optimized conditional statements, providing runtime performance benefits while maintaining type safety.

Implementation Details

• MatchProgrammer: Core logic for analyzing union types and generating conditional statements
• FunctionalMatchTransformer: Transformer integration following typia's established patterns
• Metadata-based analysis: Uses typia's metadata system to understand union structure at compile-time

The implementation provides the foundation for compile-time pattern matching and can be extended to support more sophisticated matching patterns.

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