Why do I need the shared sources file in smalltalk dialects like Pharo?

Question

the usual installation descriptions tells me that I need to run Pharo at least three files:

1. image file
2. changes file
3. source file (e.g. PharoV10.sources)

I've run Pharo 2 without the sources file and i didn't see any problem. All sources seemed to be avaiable.

So, why do I need the sources file (e.g. PharoV10.sources)?

Answer 1

The image file contains only the compiled code, not the original source code. The changes file contains source code for the stuff that you added to the system yourself but not source code for existing system classes. To get the source code for existing system classes you need the sources file.

Having said that, Smalltalk can decompile the code and produce what looks like source code if the sources file isn't available. This code will be missing proper variable names, comments and spacing. You really don't want to use decompiled source code so you need access to the sources file.