/** Compute a synchronous, deterministic SHA-256 digest of the exact UTF-8 string. */
export declare function hashString(input: string): string;
/** Compute the authoritative identity for an immutable CSS payload. */
export declare function hashCSS(css: string): string;
/**
 * Hash a candidate set using an unambiguous, versioned serialization.
 * Sorting makes Set insertion order irrelevant; JSON preserves string boundaries.
 */
export declare function hashCandidates(candidates: string[] | Set<string>): string;
export declare function isCSSContentHash(value: unknown): value is string;
export declare function extractCSSAssetHash(pathname: string): string | undefined;
/** Return an isolated route matcher so consumers cannot mutate shared identity state. */
export declare function createCSSAssetPathPattern(): RegExp;
/** Reject a forged or stale identity before it can enter a content-addressed cache. */
export declare function assertCSSContentIdentity(css: string, expectedHash: string): void;
/** Bind a style-scope profile to the exact compiler/optimizer pipeline. */
export declare function composeCSSStyleProfileHash(styleProfileHash: string, pipelineIdentity: string): string;
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