The question of which is the best VHDL editor or the best Verilog editor, will obviously depend who is asking. Different digital designers have different requirements for their HDL editors.
The following features can influence engineers in their choice for a VHDL editor and Verilog editor:

Basic features
  • Syntax highlighting
  • Templates
  • Code folding
  • Block selection / column mode
  • Auto indent
  • Configurable key bindings
Semantic features
  • Error marking
  • Code navigation
  • Semantic highlighting
Integration with:
  • Simulators
  • Synthesis tools
  • Version control systems
  • Error trackers / ticketing systems
  • Code review tools