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| 3 | <html> |
| 4 | <head> |
| 5 | <title>SWIG and MzScheme</title> |
| 6 | <link rel="stylesheet" type="text/css" href="style.css"> |
| 7 | </head> |
| 8 | |
| 9 | <body bgcolor="#ffffff"> |
| 10 | |
| 11 | <H1><a name="MzScheme"></a>21 SWIG and MzScheme</H1> |
| 12 | <!-- INDEX --> |
| 13 | <div class="sectiontoc"> |
| 14 | <ul> |
| 15 | <li><a href="#MzScheme_nn2">Creating native MzScheme structures</a> |
| 16 | </ul> |
| 17 | </div> |
| 18 | <!-- INDEX --> |
| 19 | |
| 20 | |
| 21 | |
| 22 | <p> |
| 23 | This section contains information on SWIG's support of MzScheme. |
| 24 | |
| 25 | <H2><a name="MzScheme_nn2"></a>21.1 Creating native MzScheme structures</H2> |
| 26 | |
| 27 | |
| 28 | <p> |
| 29 | Example interface file: |
| 30 | </p> |
| 31 | |
| 32 | <div class="code"> |
| 33 | <pre> |
| 34 | /* define a macro for the struct creation */ |
| 35 | %define handle_ptr(TYPE,NAME) |
| 36 | %typemap(mzscheme,argout) TYPE *NAME{ |
| 37 | Scheme_Object *o = SWIG_NewStructFromPtr($1, $*1_mangle); |
| 38 | SWIG_APPEND_VALUE(o); |
| 39 | } |
| 40 | |
| 41 | %typemap(mzscheme,in,numinputs=0) TYPE *NAME (TYPE temp) { |
| 42 | $1 = &temp; |
| 43 | } |
| 44 | %enddef |
| 45 | |
| 46 | /* setup the typemaps for the pointer to an output parameter cntrs */ |
| 47 | handle_ptr(struct diag_cntrs, cntrs); |
| 48 | </pre> |
| 49 | </div> |
| 50 | |
| 51 | <p> |
| 52 | Then in scheme, you can use regular struct access procedures like |
| 53 | </p> |
| 54 | |
| 55 | <div class="code"> |
| 56 | <pre> |
| 57 | ; suppose a function created a struct foo as |
| 58 | ; (define foo (make-diag-cntrs (#x1 #x2 #x3) (make-inspector)) |
| 59 | ; Then you can do |
| 60 | (format "0x~x" (diag-cntrs-field1 foo)) |
| 61 | (format "0x~x" (diag-cntrs-field2 foo)) |
| 62 | ;etc... |
| 63 | </pre> |
| 64 | </div> |
| 65 | |
| 66 | <p> |
| 67 | That's pretty much it. It works with nested structs as well. |
| 68 | </p> |
| 69 | |
| 70 | </body> |
| 71 | </html> |