[toronto-lisp] Effecient I/O in SBCL

I was running into problems with performance with SBCL. I want to read huge CSV files and convert ASCII representations of floats to floats. A. what's an effecient way to convert a string to a float B. what's an effecient way to read lines from a file C. what's an effecient way to split substrings from a string (I don't need to keep them around after I throw away the line) abram