p. 33: In the last paragraph, "Indexing by -1 will, of course, generate an error." should be "Note, that indexing by -1 in IDL versions before 8.0 would generate an error, but newer versions will incorrectly access the last element of the array!" p. 131: In the description for the strictarrsubs compile option, the code example starts off IDL> a = findgen(10) IDL> print, a[-1] % Attempt to subscript A with is out of range. % Execution halted at: $MAIN$ but should be IDL> a = findgen(10) IDL> print, a[10] ; in IDL 8.0+, negative indices are OK % Attempt to subscript A with is out of range. % Execution halted at: $MAIN$