Functional Problem Solving (CSC 151 2014F) : Reference
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Related Courses: [Davis (2013F)] [Rebelsky (2014S)] [Weinman (2014F)]
Misc: [Submit Questions] - [SamR] [Glimmer Labs] [CS@Grinnell] [Grinnell] - [Issue Tracker (Course)]
Believe it or not, but the error messages that you get from DrRacket occasionally contain useful information. (Okay, the always contain useful information. It may just be difficult to comprehend the information.) Read the emssages. If they make sense, follow up on the error. If they don't, check this reference or ask for help (or both).
Here are some of the more confusing error messages you might receive
and a possible explanation of those error messages. If you get other
error messages, please send them to <rebelsky@grinnell.edu>
and your faculty member so that we can add explanations to the list.
Missing gigls
./../opt/racket/collects/mred/private/snipfile.rkt:324:2: open-input-file:
cannot open input file
path: /glimmer/lib/gigls/unsafe.rkt
system error: No such file or directory; errno=2
Although we do our best to have gigls installed on every computer in
MathLAN, some get missed (e.g., because they were off when we attempted
to install gigls). Email the name of the computer to
<rebelsky@grinnell.edu>
and move to another computer.
Bad Version
../../usr/share/racket/collects/errortrace/errortrace-lib.rkt:399:2:
load-extension: bad version 5.3.6@3m (not 5.2.1@3m) from
"/glimmer/lib/louDBus/compiled/native/x86_64-linux/3m/loudbus.so"
We have two versions of DrRacket installed on the computers. This message suggests
that you are running the older version. Make sure that your launcher is configured
to use the newer version, which is in /opt/racket/bin/drracket
. If
you don't know how to configure your launcher, get help from a tutor, mentor, faculty
member, or perhaps even just an upper-level CS student. (Instructions are in the
Linux lab.)
Unbound Identifiers
drawing-XXX: unbound identifier in module in: drawing-XXX
If the unbound identifier is one of the MediaScheme/gigls procedures,
you probably forgotten to include (require gigls/unsafe)
in the top of the definitions pane. If the unbound identifier is not
one of those procedures, it just means that you forgot to define it.
(When we use define
to associate a name with a value,
Scheme says that the name (identifier) is “bound”.)
Can't Render Drawings
. . ../../rebelsky/share/lib/gigls/drawings.rkt:1130:7:
drawing-render!: Drawing does not fit within image bounds (image-width: 275
image-height: 184 drawing-left: 9453.0 drawing-top: 4231.875 drawing-right:
9591.0 drawing-bottom: 4324.375)
You will get an error message like this if you use
drawing->image
or drawing-render!
and the drawing you are using is outside the bounds of the of the
coresponding image. In this particular instance, since the image is
275 wide, the left edge of the drawing has to be smaller than 275.
It's not. It's 9453, which is much larger.
Not a Procedure
application: not a procedure;
expected a procedure that can be applied to arguments
given: 3
arguments...:
This error message suggests that you have something other than a procedure immediately after an open parenthesis. (Many of us are tempted to parenthesize parameters and such. Scheme gets upset when you do that.)