How to use the @webassemblyjs/ast.getSectionMetadata function in @webassemblyjs/ast

function applyDelete(ast: Program, uint8Buffer: Uint8Array, node: Node): State {
  const deltaElements = -1; // since we removed an element

  assertHasLoc(node);

  const sectionName = getSectionForNode(node);

  if (sectionName === "start") {
    const sectionMetadata = getSectionMetadata(ast, "start");

    /**
     * The start section only contains one element,
     * we need to remove the whole section
     */
    uint8Buffer = removeSection(ast, uint8Buffer, "start");

    const deltaBytes = -(sectionMetadata.size.value + 1) /* section id */;

    return { uint8Buffer, deltaBytes, deltaElements };
  }

  // replacement is nothing
  const replacement = [];

  uint8Buffer = overrideBytesInBuffer(

function applyDelete(ast: Program, uint8Buffer: Uint8Array, node: Node): State {
  const deltaElements = -1; // since we removed an element

  assertHasLoc(node);

  const sectionName = getSectionForNode(node);

  if (sectionName === "start") {
    const sectionMetadata = getSectionMetadata(ast, "start");

    /**
     * The start section only contains one element,
     * we need to remove the whole section
     */
    uint8Buffer = removeSections(ast, uint8Buffer, "start");

    const deltaBytes = -(sectionMetadata.size.value + 1); /* section id */

    return { uint8Buffer, deltaBytes, deltaElements };
  }

  // replacement is nothing
  const replacement = [];

  uint8Buffer = overrideBytesInBuffer(

function applyAdd(ast, uint8Buffer, node) {
  var deltaElements = +1; // since we added an element

  var sectionName = getSectionForNode(node);
  var sectionMetadata = getSectionMetadata(ast, sectionName); // Section doesn't exists, we create an empty one

  if (typeof sectionMetadata === "undefined") {
    var res = createEmptySection(ast, uint8Buffer, sectionName);
    uint8Buffer = res.uint8Buffer;
    sectionMetadata = res.sectionMetadata;
  }
  /**
   * check that the expressions were ended
   */


  if (isFunc(node)) {
    // $FlowIgnore
    var body = node.body;

    if (body.length === 0 || body[body.length - 1].id !== "end") {

function applyDelete(ast, uint8Buffer, node) {
  var deltaElements = -1; // since we removed an element

  assertHasLoc(node);
  var sectionName = getSectionForNode(node);

  if (sectionName === "start") {
    var sectionMetadata = getSectionMetadata(ast, "start");
    /**
     * The start section only contains one element,
     * we need to remove the whole section
     */

    uint8Buffer = removeSections(ast, uint8Buffer, "start");

    var _deltaBytes = -(sectionMetadata.size.value + 1)
    /* section id */
    ;

    return {
      uint8Buffer: uint8Buffer,
      deltaBytes: _deltaBytes,
      deltaElements: deltaElements
    };

function applyAdd(ast: Program, uint8Buffer: Uint8Array, node: Node): State {
  const deltaElements = +1; // since we added an element

  const sectionName = getSectionForNode(node);

  let sectionMetadata = getSectionMetadata(ast, sectionName);

  // Section doesn't exists, we create an empty one
  if (typeof sectionMetadata === "undefined") {
    const res = createEmptySection(ast, uint8Buffer, sectionName);

    uint8Buffer = res.uint8Buffer;
    sectionMetadata = res.sectionMetadata;
  }

  /**
   * check that the expressions were ended
   */
  if (isFunc(node)) {
    // $FlowIgnore
    CHECK_END(node.body);
  }

const getNextTypeIndex = ast => {
	const typeSectionMetadata = t.getSectionMetadata(ast, "type");

	if (typeSectionMetadata === undefined) {
		return t.indexLiteral(0);
	}

	return t.indexLiteral(typeSectionMetadata.vectorOfSize.value);
};

const getNextFuncIndex = (ast, countImportedFunc) => {
	const funcSectionMetadata = t.getSectionMetadata(ast, "func");

	if (funcSectionMetadata === undefined) {
		return t.indexLiteral(0 + countImportedFunc);
	}

	const vectorOfSize = funcSectionMetadata.vectorOfSize.value;

	return t.indexLiteral(vectorOfSize + countImportedFunc);
};

const getNextTypeIndex = ast => {
	const typeSectionMetadata = t.getSectionMetadata(ast, "type");

	if (typeSectionMetadata === undefined) {
		return t.indexLiteral(0);
	}

	return t.indexLiteral(typeSectionMetadata.vectorOfSize.value);
};

const getNextFuncIndex = (ast, countImportedFunc) => {
	const funcSectionMetadata = t.getSectionMetadata(ast, "func");

	if (funcSectionMetadata === undefined) {
		return t.indexLiteral(0 + countImportedFunc);
	}

	const vectorOfSize = funcSectionMetadata.vectorOfSize.value;

	return t.indexLiteral(vectorOfSize + countImportedFunc);
};