In Eclipse a project can have zero to many project natures. Various plug-ins provide functionality for a project if it is tagged with a specific nature.
For example the SystemVerilog plug-in indexes a project (for autocomplete or navigation)
only if it has the Verilog Nature.
Of course if you created
a project using a wizard from the SystemVerilog plug-in, the Verilog Nature is automatically added and you don't have to
worry about it.
But what if you work on a project for which you want both e and SystemVerilog indexing? You need to configure the project to have the natures you need.
To turn on/off a specific nature for a project, select the project in Navigator and chose the relevant action from the right click menu.
Project natures are stored in the project definition (in the .project file).