9 Teaching Languages
The teaching language are implemented via the tools interface and thus not part of DrRacket proper, but one helper library is documented here.
| (require lang/htdp-langs-save-file-prefix) | |
| package: htdp-lib | |
These strings are used as the prefix in a file saved while using the teaching
languages. Each string is on a separate line in the saved file.
procedure
(htdp-file-prefix? ip) → boolean?
ip : input-port?
Determines if the contents of ip is one of the possible prefixes that
DrRacket saves at the beginning of a teaching language file.
In the case that this function returns #t, it consumes the entire prefix from ip (and discards it). In the case that this function returns #f, it does not consume anything from ip.