SubEthaEdit
General purpose plain text editor for macOS
...Great for comparing multiple places, keeping a reference section open, or following others. Use your desired flavor of regex for the search. From simple shell to full power ruby style. Have multiple search result windows at the same time. Constrain search to just preselected parts of your document. See the structure and depth of your documents in the line number and folding ribbon. Fold text away based on depths or however, you want. Select lines and/or depth easily with a single click. Select to matching braces by a simple double click.