This shows autocomplete in action in the Phrogram code editor.  To bring up the autocomplete list, just type CTRL+J when in the code editor.  If you have begun typing a word, the list of suggested autocomplete will be filtered to things that match what you have begun typing.

This shows the use of line numbers in Phrogram, including to identify and locate errors in the code editor

This shows and described the use of the splitter controls in the Phrogram code editor

This shows the different elements of Phrogram's code editor