presto-main/src/main/java/io/prestosql/sql/planner/ExpressionSymbolInliner.java/ExpressionSymbolInliner/inlineSymbols
class ExpressionSymbolInliner:    public static Expression inlineSymbols(Function<Symbol, Expression> mapping, Expression expression)
    {
        return new ExpressionSymbolInliner(mapping).rewrite(expression);
    }