How to use the @angular/language-service/src/locate_symbol.locateSymbol function in @angular/language-service

function getHover(info) {
        var result = locate_symbol_1.locateSymbol(info);
        if (result) {
            return { text: hoverTextOf(result.symbol), span: result.span };
        }
    }
    exports.getHover = getHover;

function getDefinition(info) {
        var result = locate_symbol_1.locateSymbol(info);
        return result && result.symbol.definition;
    }
    exports.getDefinition = getDefinition;