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11 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


htdp-save-file-prefix : (listof string?)

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.


(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.