Python Implementation
NestedText is a file format for holding structured data to be entered, edited, or viewed by people. It organizes the data into a nested collection of dictionaries, lists, and strings without the need for quoting or escaping. A unique feature of this file format is that it only supports one scalar type: strings. While the decision to eschew integer, real, date, etc. types may seem counter intuitive, it leads to simpler data files and applications that are more robust.
NestedText is convenient for configuration files, address books, account information, and the like. Because there is no need for quoting or escaping, it is particularly nice for holding code fragments. Here is an example of a file that contains a few addresses: