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Authored math alternatives lose priority over structure · case 02

Authored math alternatives lose priority over structure.

Member previewVariant 2 · 3 implementations · 10 checks per implementation

Case contract

Input AST limited to token(value), row(children), fraction(two children), power(two children), root(one child), fenced(children), annotation(primary,alternative) encoded dict kind, value, children, alternative. Empty rows expose empty string. Tokens preserve value. Fraction says fraction numerator over denominator end fraction; power says base to power exponent; root says square root child end root; fenced says open contents close. Empty child output omitted between single spaces. Annotation uses a nonempty alternative verbatim, otherwise its sole primary child. Unknown kinds return unsupported; wrong arity returns malformed without traversing children.

Why this case matters

Offline accessibility bridge model with explicit policy; useful for testing semantic API adapters independently of browser implementations.

One recorded failure

Sample boundary fixture

This sample comes from the broken implementation of a controlled reproducer.

Boundary fixture	Actual	Expected	Outcome
contract fixture 5	`"x"`	`"custom"`	Failed

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