Read lines from file thats in a variable

[Neil_H]

Okay, so I read in a file like this:

var testFileAll = readFile(testFilePath)

And now I want to do some work on each line, yet this doesn't work:

for line in lines(testFileAll):
    echo line

So is there no lines procedure for a file that's been read in? I really don't 
want to have to copy between memfiles, streams etc just to access each line.