A simple library for reading simple property files.

Package Information

Version0.0.2 (2016-Jan-02)
CopyrightCopyright © 2013, Peter Wood.
AuthorsPeter Wood
Registered byPeter Wood


To use this package, put the following dependency into your project's dependencies section:




Proper-D is a simple library of functions for interacting with property files (i.e. files that contain simple name value pairs). This is similar in nature to the functionality offered by the java.util.Properties class in Java but with a D twist. The library effectively provides a very basic file format for use as things like of configuration files.


The library uses the dub package manager so you will need to install that. To build the unit tests for the library clone the repository and, from the root directory of the repository copy, run this command...

   dub build --build=unittest

Once this successfully completes there should be an executable created in the same directory called proper-d.exe on Windows or proper-d on Linux. Run this executable to execute the unit tests.

In terms of using the library the simplist thing to do is to copy the main source file (source/proper-d.d) into your project. It has no dependencies beyond elements of the D standard library.


In Java the Properties class completely wraps the functionality for handling property files but D provides associative arrays which would obviate the need for a complete class. With this in mind the Proper-D code is worked around creating associative arrays of strings indexed by strings. To make use of Proper-D include the source file in your project and then import it into the code to use it with a line such as...

   import properd;

Next you can either load a file of properties or provide a string that can be parsed into an associative array. Some examples follow...

   // Load the ./examples.cfg file as a property file.
   auto properties = readProperties("./examples.cfg");

   // Same as before but specified via a File object.
   properties = readProperties(new File("./examples.cfg", "r"));

   // Parse a string of text into a property list.
   properties = parseProperties("first = One\nsecond = 2\nThird = 3.14");

All of the function calls shown above return associative arrays of type string indexed by string (i.e. `string[string]`). No interpretation of the data is made but the library does provide an as() function that will attempt to convert the values from an associative array to a specific type. The following is an example of using this function...

   auto value1 =!(int)("second");

Here an attempt is made to convert the value indexed under the key "second" in the associative array `properties to an int`. If this fails then an exception will be raised. A specialization of this template function is provided for conversion of values to the bool type. This specialization will recognise "true", "1", "on" and "yes" (test is case insensitive) as being a boolean value of true. Anything else is false.


Consult the license.txt file for licensing information.

Available versions

0.0.2 0.0.1 ~master ~1.0.0 ~0.0.1