Errata for Concrete Abstractions

This web page lists errors that have been discovered in Concrete Abstractions: An Introduction to Computer Science Using Scheme, by Max Hailperin, Barbara Kaiser, and Karl Knight. We welcome additional reports of errors; please email

The errata are listed below in order of page number. We also have an alternate version of the list in order of date (from most recent to least), to make it easier to find newly added errata.

When a line number is negative, it means to count lines up from the bottom of the page. Line numbers do not count the header line at the top of the page (with page number, etc.). Other than that, all textual lines are counted, even if they are tables, figure captions, section headings, exercise headings, or textual lines that contain graphical images. Any graphical image not contained in a textual line is not counted, even if the image contains text within it.
iv3Add "Cover Relief: Frank Lloyd Wright"25-Nov-1998
viii10Capitalize "based".31-Aug-1998
viii17Insert "An Application:" before "Dictionaries".31-Aug-1998
viii19Capitalize "oriented".31-Aug-1998
viii21Capitalize "oriented".31-Aug-1998
viii23Capitalize "oriented".31-Aug-1998
xiii4Insert after "exception": "to our usual adherence to R4RS".28-Aug-1998
xvi1Add new paragraph: "Mark Gritter wrote the SLIME applet, a computer simulator for Chapter 11 that is included on our web site."25-Nov-1998
124Insert "Fahrenheit" after "degree".2-Jan-2007
16-4Delete "naturally".25-Nov-1998
42-6Delete hyphen in "pin-wheel".28-Aug-1998
458Replace "Appendix A" by "The Appendix"10-Sep-1998
643Replace "then" by "the".4-May-2004
92-10After "(1)" insert "When".5-Nov-2004
10421-22Replace "recursively sum the two halves" by "sum the two halves the same way"24-May-2001
11721Replace "42" by "41".15-Mar-2005
142-3Insert "(perhaps named ok-input?)" before "to".25-Nov-1998
1795Replace "perfect" by "positive perfect".5-Nov-2004
1797Replace "even" by "positive even".5-Nov-2004
1872Replace "than than" by "than".4-May-2004
1925Replace "parenthesis" with "parentheses".22-Nov-1999
2031Change heading to "Is There More to Intelligence? (Continued)"4-Sep-1998
20322Insert a comma after "human".22-Nov-1999
2482Replace "the the" by "the".4-May-2004
2516Delete last four parentheses, then insert new (seventh) line of code aligned with first line: (else (error "illegal sequence operation" op))))))18-Jan-2000
263-6After "images" insert "or drawing media".4-May-2004
2686Before "transformed" insert "be".4-May-2004
270-10Replace "twice a" with "twice as".13-Dec-2007
270-9Add "in each dimension" after "big".10-May-2007
270-8Add "in each dimension" after "big".10-May-2007
274-6Replace "be be" by "be".4-May-2004
296Fig. 10.3Add an arc through A1's right edge to indicate singleton list.23-Mar-2007
327-2Change "a for" to "an uncons"19-Mar-2003
38215Change "2" to "3" (in "again, for n>2").16-Jun-1999
40020Change the first "1" to "0".5-Mar-2003
417-2Insert "limited history recurrence" into list between "knapsack problem" and "Stirling numbers of the second kind".13-Nov-2000
4202Capitalize "based".31-Aug-1998
432-2Replace "precedures" by "procedures".25-Oct-2001
4542Replace "hold must hold" by "hold".4-May-2004
4736Delete the comma before "that".11-Jun-1999
4797Insert "in the input" between "early" and "as".6-Nov-2000
482-1Add: "c. Modify make-initial-global-environment to not use make-mini-scheme-version-of."15-Nov-2001
4862Capitalize "oriented".31-Aug-1998
4874Capitalize "oriented".31-Aug-1998
49613,14Delete spaces after opening quotation marks.15-Nov-2001
512-2Delete "(However, the methods don't need to have been set yet.)".13-Nov-2000
51316Insert "init," (in code font) before "add".22-Nov-1999
5171Capitalize "oriented".31-Aug-1998
523-12Replace "Section 10.3" by "page 302"25-Nov-1998
5771Replace "FIFTEEEN" by "FIFTEEN"28-Nov-2001
5954Delete "if(option == 6)".2-Jan-2001
634-2Delete space between "setInitial" and "Amount".10-May-2004
654-4Replace the URL with
6619Insert "limited history recurrence" (between "LIFO" and "line") with page number 40613-Nov-2000
66422Insert "onto technique" (between "one-layer thinking maxim" and "opcode") with page numbers 181-182, 219.2-Jan-2001
6694Replace "traversal, post-order, 284" by "traversal, tree, 218-220"6-Dec-2000

For more information, see the parent web page, or contact Max Hailperin:
Mathematics and Computer Science Department
Gustavus Adolphus College
800 W. College Avenue
St. Peter, MN 56082
Revision 1.26 as of 2007/12/13 13:57:57