In addition to the powerful features of an Eclipse editor, the VHDL editor that comes with Sigasi HDT supports a number of advanced editing features which are specifically useful for VHDL editing. These are described in this chapter.
Block selection is an alternative for standard (paragraph) selection. Block selection mode differs from standard selection mode in that it allows to select rectangular regions, or to set the cursor over multiple lines. Block selection is ideal for selecting vertical regions, for example a column of a table or all port names in a port map.
To toggle between normal and block selection modes use Alt+Shift+A or Edit ‣ Toggle Block Selection
You can align the current selection with Edit ‣ Align. Aligning is done by looking at a common delimiter string in consective lines. The supported delimiter strings are: <= , := => :
Blank lines and comment lines are ignored. Both tabs and spaces are supported.
You can easily move lines up and down by pressing Alt+Up and Alt+Down.
You can easily clean up the indentation and remove trailing whitespaces in the current selection, by pressing Ctrl+I.
VHDL is case insensitive. However, for clarity’s sake it is best to keep the case of identifiers and keywords consistent throughout the project.
By right-clicking in the editor window, you can access the Fix Case refactoring. This action cleans up the case of the keywords and indentifiers in your file as follows:
Stuttering is an editing technique popularized by Emacs, that lets you type certain things really fast. Stuttering means that you tap a certain key twice and it expands to something more complex. For example, press the period key (.) twice, and the editor will expand it to a right arrow (=>). Stuttering works like double clicking: if you type keys slowly, the stuttering mechanism will not be triggered.
The following stuttering keys are available:
| Keys | Effect |
| ,, | <= |
| .. | => |
| :: | := |
Stuttering can be disabled or enabled in Window ‣ Preferences‣Sigasi (VHDL)‣Editor‣Enable stuttering.