(gobject:define-genum "GtkWrapMode" wrap-mode
  (:export t
   :type-initializer "gtk_wrap_mode_get_type")
  (:none 0)
  (:char 1)
  (:word 2)
  (:word-char 3))  

:none

Do not wrap lines, just make the text area wider.

:char

Wrap text, breaking lines anywhere the cursor can appear between characters, usually. If you want to be technical, between graphemes, see the pango:log-attrs function.

:word

Wrap text, breaking lines in between words.

:word-char

Wrap text, breaking lines in between words, or if that is not enough, also between graphemes.