private void replaceSymbols(List symbols, boolean alias) {
for (int i = 0; i < symbols.size(); i++) {
Object symbol = symbols.get(i);
if (symbol instanceof SingleElementSymbol) {
SingleElementSymbol ses = (SingleElementSymbol)symbol;
SingleElementSymbol replacmentSymbol = replaceSymbol(ses, alias);
symbols.set(i, replacmentSymbol);
}
}
}