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34 lines
893 B
Text
34 lines
893 B
Text
-*- text -*-
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This directory includes an example program for extending Guile with a
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new (and even useful) data type.
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To build the example, simply type
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make box
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in this directory.
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The resulting `box' program is a Guile interpreter which has one
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additional data type called `box'.
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A box is simply an object for storing one other object in. It can be
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used for passing parameters by reference, for example. You simply
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store an object into a box, pass it to another procedure which can
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store a new object into it and thus return a value via the box.
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Box objects are created with `make-box', set with `box-set!' and
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examined with `box-ref'. See the following example session for usage
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details:
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$ ./box
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guile> (define b (make-box))
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guile> b
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#<box #f>
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guile> (box-set! b '(list of values))
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guile> b
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#<box (list of values)>
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guile> (box-ref b)
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(list of values)
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guile> (quit)
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$
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