CaptureInputFromEditor opens a temporary file in a text editor and returns the written bytes on success or an error on failure.

GetOptionValue fetches value for a given option in command line arguments.

GetPreferredEditorFromEnvironment returns the user's editor as defined by the `$EDITOR` environment variable, or the `DefaultEditor` if it is not set.

OpenFileInEditor opens filename in a text editor.

SliceIndex returns index of a given element in slice.

DefaultEditor is vim.

PreferredEditorResolver is a function that returns an editor that the user prefers to use, such as the configured `$EDITOR` environment variable.