/**
 * @fileoverview `mathmlText` — what a MathML formula reads as once its markup is gone. A
 * presentation tree encodes most of its operators as structure rather than as characters: a
 * radical is an `<msqrt>`, an exponent is the second child of an `<msup>`, a fraction bar is an
 * `<mfrac>`, and a fence can live in an attribute. Emptying the tree of tags and joining its
 * text deletes every one of them — `√m ∈ ℚ₅` reads `m∈Q5` — so the region is read instead:
 *
 * 1. **A TeX annotation, as deposited.** A deposit that carries its expression a second time as
 *    TeX (`<annotation encoding="application/x-tex">`) has already written the linear form, and
 *    losslessly; it replaces the presentation tree rather than joining it, so the formula still
 *    reaches the reader once.
 * 2. **Otherwise, the tree written out** in a linear notation that keeps the structure: `x_i`,
 *    `A^{−1}`, `∑_{i=1}^N`, `^{33}Si`, `√(m)`, `√[3](x)`, `(Np)/(N−p)`, rows of a table joined
 *    by `; `. Every other copy of the expression — a Content MathML `<annotation-xml>`, a
 *    `<semantics>` wrapper's later children — is dropped for the same reason the TeX replaces
 *    the tree.
 * 3. **Any other element** is spelled `name(child, …)` over its children, so a construct with no
 *    linear form stays visible and intact rather than reading as a different formula.
 *
 * The reading is linear in the region and costs nothing on the call stack: one tag scan builds
 * the tree, one pass over it in reverse document order finishes every node after its children,
 * and each node's text is built by concatenation rather than by copying its children's text, so
 * a region nested thousands of elements deep costs what a flat one does.
 * @module services/crossref/mathml
 */
/**
 * Read a MathML region — the content between a `<math>` element's tags — as one line of text.
 * The caller supplies the block boundary the region leaves in the sentence around it.
 */
export declare function mathmlText(inner: string): string;
//# sourceMappingURL=mathml.d.ts.map