Kotlin이 Objective-C에 매핑되는 방식

When you build for iOS, Kotlin compiles into an Objective-C framework. Swift then sees your shared code through that Obj-C lens.

Swift has no direct Kotlin bridge, but it interops perfectly with Objective-C. So Kotlin targets Obj-C, and Swift reads it from there.

A Kotlin class maps to an Obj-C class of the same name. Swift can construct and use it almost like any native type.

Top-level Kotlin functions land on a generated helper class, while member functions become methods Swift can call directly.

A Kotlin nullable type like String? becomes a Swift optional, so you unwrap it with the usual if-let or guard.

Some Kotlin names clash with Obj-C rules and get auto-renamed. A trailing underscore or prefix may appear on the Swift side.

Kotlin Int and friends arrive in Swift as KotlinInt boxes when nullable or generic. Plain non-null primitives map to native Int.

A Kotlin companion object appears in Swift as a static .companion accessor, letting you reach factory functions and constants.

Kotlin enums become Obj-C-style enums, but sealed classes arrive as a class hierarchy Swift must check with is/as casts.

Everything exported lands under a single framework module you import in Swift, like import shared, exposing all your types.

Not every Kotlin feature survives the bridge cleanly. Knowing this mapping helps you design APIs that feel natural in Swift.

Kotlin compiles to an Obj-C framework: classes map to classes, nullables to optionals, companions to statics. Design with the bridge in mind. 🙂