Notepad++ provides 2 types of features:
- Auto-completion that read the open file and provide suggestion of words and/or functions within the file
- Suggestion with the arguments of functions (specific to the language)
Based on what you write, it seems what you want is auto-completion on function only + suggestion on arguments.
To do that, you just need to change a setting.
- Go to
Settings>Preferences...>Auto-completion - Check
Enable Auto-completion on each input - Select
Function completionand notWord completion - Check
Function parameter hint on input(if you have this option)
On version 6.5.5 of Notepad++, I have this setting
Some documentation about auto-completion is available in Notepad++ Wiki.