As EvoAl uses a domain-specific language that supports an import mechanism, it must find the files that are used. Pitifully, the two main use cases have a slightly different lookup strategy.
Eclipse search path
In Eclipse, your DSL files will be located in a project (it is sufficient to create a general project). When you create your first DSL file, Eclipse will ask if you want to add Xtext capabilities. Please answer yes here. In your DSL file, you can import everything included in the project.
Importing pre-defined EvoAl files
At the moment, you need to add the definition files from EvoAl to your Eclipse project. The easiest way is to create a new folder in your project and specify it as a symbolic link in the advanced settings.
Importing files from a different Eclipse project
Add a project dependency if you want to import files from another project. Therefore, you have to add the dependency in Eclipse's project settings.
Command-line search path
Things are a little easier when working at the command line. EvoAl will find all built-in definitions automatically as they are contained in the program code. If your files are split over several locations on your disk, you can specify an additional search path by specifying the parameter -Bcore:search-path=.... You can add a list of paths that are separated by the OS-specific path separator (; on Windows, and : on MacOS and Linux).