port some code from another language to the one you want to learn.
Well, this week I though I'd have a go at the third. Picking something that was well writen to start with, I decided to use binc, an extremely well writen imap server which is writen in C++, and see how it converts to D.
Rather than attacking the core imap bit, I decided to start with the MimeDocument decoding part. something relatively self contained, and conceptually quite simple. Most of the Porting involved bringing together Classes that had methods defined in multiple files (as seems common with C++), and merging them into nice classes in D.
While most of it will probably end up untested until it's all ported, one single method stood out as a good simple test of working with D. - Searching for a string (or delimiter) in a stream.
Obviously, one of the things that happens with an imap server, is that it has to scan a email message, and find out how what makes up the email (eg. attachments, different mimetypes and how they are nested. A brute force approach would be to load the whole message into memory, and just scan through looking for the sections. However, since email messages can frequently be over 5Mb, It's obviously horribly inefficent. So the existing code used a simple C++ method to search for a delimiter.
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