void expectNumberOrSymbol ( Node n , JSType type , String msg ) { if ( ! type . matchesNumberContext ( ) && ! type . matchesSymbolContext ( ) ) { mismatch ( n , msg , type , NUMBER_SYMBOL ) ; } }
Expect the type to be a number or string or a type convertible to a number or symbol . If the expectation is not met issue a warning at the provided node s source code position .