Kotlin Programming Cookbook

How it works…

BufferedReader provides us with a lot of methods that we can use to read contents of the file or input stream line by line. Using useLines(), we get a sequence of lines that we can then iterate on using forEach. A user may terminate the iteration loop, so the caller needs to close the BufferedReader, which is what useLines() does. We can only iterate over the sequence returned once.

The syntax for useLines() is this:

inline fun <T> File.useLines(    charset: Charset = Charsets.UTF_8,     block: (Sequence<String>) -> T): T