R: eval(parse(…)) is often suboptimal

Question

require(\'fortunes\')
fortune(\'106\')
Personally I have never regretted trying not to underestimate my own future stupidity.
   -- Greg Snow (explaining why eval(pa         


        

Answer 1

Actually the list probably looks a bit different. The '$' convention is somewhat misleading. Try this:

dat[["orders"]][[ or_ID ]][["price"]]

The '$' does not evaluate its arguments, but "[[" does, so or_ID will get turned into "5810584".