Method parseUnionOrIntersectionType

internal/parser/parser.go:2644–2664

(operator ast.Kind, parseConstituentType func(p *Parser) *ast.TypeNode)

}

func (p *Parser) parseUnionOrIntersectionType(operator ast.Kind, parseConstituentType func(p *Parser) *ast.TypeNode) *ast.TypeNode {
	pos := p.nodePos()
	isUnionType := operator == ast.KindBarToken
	hasLeadingOperator := p.parseOptional(operator)
	var typeNode *ast.TypeNode
	if hasLeadingOperator {
		typeNode = p.parseFunctionOrConstructorTypeToError(isUnionType, parseConstituentType)
	} else {
		typeNode = parseConstituentType(p)
	}
	if p.token == operator || hasLeadingOperator {
		types := make([]*ast.Node, 1, 8)
		types[0] = typeNode
		for p.parseOptional(operator) {
			types = append(types, p.parseFunctionOrConstructorTypeToError(isUnionType, parseConstituentType))
		}
		typeNode = p.createUnionOrIntersectionTypeNode(operator, p.newNodeList(core.NewTextRange(pos, p.nodePos()), p.nodeSliceArena.Clone(types)))
		p.finishNode(typeNode, pos)
	}
	return typeNode
}

func (p *Parser) createUnionOrIntersectionTypeNode(operator ast.Kind, types *ast.NodeList) *ast.Node {
	switch operator {