11 Teaching Languages

▼ |  | Dr Racket Plugins

1 | Tool support for #lang-based Languages
2 | Implementing Dr Racket Plugins
3 | Adding Languages to Dr Racket
4 | Creating New Kinds of Dr Racket Frames
5 | Extending the Existing Dr Racket Classes
6 | Expanding the User’s Program Text and Breaking
7 | Editor Modes
8 | Plugin Capabilities
9 | Check Syntax
10 | Cooperating with Background Check Syntax
11 | Teaching Languages
12 | Signatures
13 | drracket: get/ extend
14 | drracket: unit
15 | drracket: language
16 | drracket: language-configuration
17 | drracket: debug
18 | drracket: rep
19 | drracket: frame
20 | drracket: help-desk
21 | drracket: eval
22 | drracket: modes
23 | drracket: module-language-tools
24 | drracket: module-language
25 | drracket: tracing
26 | drracket: init
27 | Backwards Compatibility
| Index

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htdp-save-file-prefix
htdp-file-prefix?

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## 11 Teaching Languages🔗ℹ

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

> value 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.

> 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.

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