index.js
function StackMapper(sourcemap) {
  if (!(this instanceof StackMapper)) return new StackMapper(sourcemap);
  if (typeof sourcemap !== 'object') 
    throw new Error('sourcemap needs to be an object, please use convert-source-map module to convert it from any other format\n' +
                    'See: https://github.com/thlorenz/stack-mapper#obtaining-the-source-map');

  this._sourcemap = sourcemap;
  this._prepared = false;
}
function StackMapper(sourcemap) {
  if (!(this instanceof StackMapper)) return new StackMapper(sourcemap);
  if (typeof sourcemap !== 'object') 
    throw new Error('sourcemap needs to be an object, please use convert-source-map module to convert it from any other format\n' +
                    'See: https://github.com/thlorenz/stack-mapper#obtaining-the-source-map');

  this._sourcemap = sourcemap;
  this._prepared = false;
}
function StackMapper ( sourcemap ) { if ( ! ( this instanceof StackMapper ) ) return new StackMapper ( sourcemap ) ; if ( typeof sourcemap !== 'object' ) throw new Error ( 'sourcemap needs to be an object, please use convert-source-map module to convert it from any other format\n' + 'See: https://github.com/thlorenz/stack-mapper#obtaining-the-source-map' ) ; this . _sourcemap = sourcemap ; this . _prepared = false ; }
Creates a Stackmapper that will use the given source map to map error trace locations

@name StackMapper
@private
@constructor
@param {Object} sourcemap
Creates a Stackmapper that will use the given source map to map error trace locations