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| <title>SWIG and MzScheme</title> |
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| <H1><a name="MzScheme"></a>24 SWIG and MzScheme</H1> |
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| <ul> |
| <li><a href="#MzScheme_nn2">Creating native MzScheme structures</a> |
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| <p> |
| This section contains information on SWIG's support of MzScheme. |
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| <H2><a name="MzScheme_nn2"></a>24.1 Creating native MzScheme structures</H2> |
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| <p> |
| Example interface file: |
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| <pre> |
| /* define a macro for the struct creation */ |
| %define handle_ptr(TYPE,NAME) |
| %typemap(argout) TYPE *NAME{ |
| Scheme_Object *o = SWIG_NewStructFromPtr($1, $*1_mangle); |
| SWIG_APPEND_VALUE(o); |
| } |
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| %typemap(in,numinputs=0) TYPE *NAME (TYPE temp) { |
| $1 = &temp; |
| } |
| %enddef |
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| /* setup the typemaps for the pointer to an output parameter cntrs */ |
| handle_ptr(struct diag_cntrs, cntrs); |
| </pre> |
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| Then in scheme, you can use regular struct access procedures like |
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| <pre> |
| ; suppose a function created a struct foo as |
| ; (define foo (make-diag-cntrs (#x1 #x2 #x3) (make-inspector)) |
| ; Then you can do |
| (format "0x~x" (diag-cntrs-field1 foo)) |
| (format "0x~x" (diag-cntrs-field2 foo)) |
| ;etc... |
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| That's pretty much it. It works with nested structs as well. |
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