/**
 * Effect type registry — maps effect names to their argument and return types.
 *
 * Effect declarations like `effect @llm.complete(String) -> String` register
 * here. During inference, `perform(@llm.complete, prompt)` checks the arg
 * type and returns the declared return type (instead of Unknown).
 *
 * For Phase C (Step 7), this also informs handler clause typing:
 * - The handler parameter gets the effect's arg type
 * - `resume` gets the effect's return type as its parameter type
 */
import type { Type } from './types';
export interface EffectDeclaration {
    /** The argument type passed to perform. */
    argType: Type;
    /** The return type — what perform() returns, what resume() accepts. */
    retType: Type;
}
export interface EffectRegistrySnapshot {
    entries: [string, EffectDeclaration][];
    builtinNames: string[];
}
/**
 * Register an effect's type declaration.
 *
 * Silently skips names in `builtinEffectNames` so that user-level
 * `effect @name(T) -> U` declarations cannot overwrite a builtin
 * effect's signature. HandlerWrapperInfo for wrappers like
 * `effectHandler.chooseRandom` captures arg/ret types by value at
 * module-registration time, but the active handled signatures pushed
 * at perform sites are also derived from the registry — letting users
 * stomp on those would mis-type perform calls inside handler wrappers.
 * `initBuiltinEffects` uses `declareBuiltinEffect` below to install the
 * builtins without going through this guard.
 */
export declare function declareEffect(name: string, argType: Type, retType: Type): void;
/** Look up an effect's declaration. Returns undefined if not declared. */
export declare function getEffectDeclaration(name: string): EffectDeclaration | undefined;
/** Get the return type of a declared effect, or Unknown if not declared. */
export declare function getEffectReturnType(name: string): Type;
/** Get the argument type of a declared effect, or Unknown if not declared. */
export declare function getEffectArgType(name: string): Type;
/** Snapshot the current registry so nested import typechecking can restore it. */
export declare function snapshotEffectRegistry(): EffectRegistrySnapshot;
/** Restore a previously captured registry snapshot. */
export declare function restoreEffectRegistry(snapshot: EffectRegistrySnapshot): void;
/** Reset user-declared effects (called at the start of each typecheck pass).
 * Builtin effects are preserved. */
export declare function resetUserEffects(): void;
/** Reset the entire registry (for testing). */
export declare function resetEffectRegistry(): void;
/** Register built-in Dvala effects with known types. */
export declare function initBuiltinEffects(): void;