Computation hGetContents hdl returns the list of characters corresponding to the unread portion of the channel or file managed by hdl, which is immediate closed.

Items are read strictly from the input Handle.

This operation may fail with:

• isEOFError if the end of file has been reached.

The getContents operation returns all user input as a single string, which is read stirctly (same as hGetContents stdin).

The readFile function reads a file and returns the contents of the file as a string. The file is read strictly, as with getContents.

The interact function takes a function of type String->String as its argument. The entire input from the standard input device is passed to this function as its argument, and the resulting string is output on the standard output device.