Reading plain text file database tables

[Li Dongfeng]

Do we have a module to read plain text file
database tables?

All the data management software, e.g. excel,
dBase, SAS, etc., support input/output a table 
from/to a plain text file, fields can be separated
by their column position, by spaces, by tabs,
by commas, etc.

How can we read this kind of file into a matrix like
structure(list of lists)? I have written one reading
files with fixed-width fields. For delimited files,
simply using string.split work most of the time, but
fails reading lines like

  "Peter Thomson"  25  36

or even 

  "Peter\" Thomson" 25 36

I think this is a common task, so maybe someone has
already given a very good solution.

Li Dongfeng