The 2htdp/batch-io library contains the useful read-csv-file procedure for reading a CSV file into a list. It takes a filename as its argument. Unfortunately, it does not take a string containing CSV as its argument. Suppose I have a CSV in a string variable and I want to use read-csv-file to parse it. Is there a way to avoid saving the CSV to a file just to be able to parse the CSV?
The documentation says:
reads the standard input device (until closed) or the content of file f and produces it as a list of lists of comma-separated values.
The standard input feature could probably be exploited to achieve this, but I don't know how to proceed with this idea.
I found a way to make read-csv-file read from a string instead:
> (require 2htdp/batch-io)
> (define csv-string "one,one,one\ntwo,two,two")
> (parameterize ([current-input-port (open-input-string csv-string)])
(read-csv-file 'stdin))
'(("one" "one" "one") ("two" "two" "two"))
This works by changing the standard input to be the CSV string.
@Ryan Schaefer's answer about simulate-file is great, but I feel a bit uncomfortable with using functionality that is still "under development" and not properly documented. As simulate-file's documentation says:
Note: this form is under development and will be documented in a precise manner after it is finalized and useful for a wide audience.