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git-svn-id: svn://svn.savannah.gnu.org/nano/trunk/nano@3130 35c25a1d-7b9e-4130-9fde-d3aeb78583b8

src/text.c

@@ -974,6 +974,9 @@ filestruct *backup_lines(filestruct *first_line, size_t par_len)
     }
 #endif
 
+    /* Note: par_len will be one greater than the number of lines
+     * between current and filebot if filebot is the last line to be
+     * backed up. */
     assert(par_len > 0 && openfile->current->lineno + par_len <=
 	filebot->lineno + 1);