我有一个球拍模块hw.rkt:
#lang racket/base
(provide hw)
(define (hw) (displayln "Hello, world!"))
我想编写一个嵌入Racket运行时的C程序并应用(hw)
过程。
示例代码here演示了如何嵌入Racket运行时并应用racket/base
中的过程,或者读取和评估S表达式,但我已经有了没有运气修改此代码以允许访问(hw)
程序。
This page似乎是说可能通过首先使用raco ctool --c-mods
将hw.rkt编译为hw.c来做我想做的事情,这只是工作原理我尝试时很好,但我仍然无法访问(hw)
程序。
如果某人可以发布完整的示例程序,或者只是描述要使用哪些C函数,我将非常感激。从那里我可以弄清楚剩下的。
编辑以提供我尝试过的事情的示例。
我修改了示例程序以摆脱" evaluate命令行参数"咬并直接跳到REPL以便我可以试验。因此(使用" hw.c"运行raco ctool --c-mods hw.c ++libs racket/base hw.rkt
的结果):
#define MZ_PRECISE_GC
#include "scheme.h"
#include "hw.c"
static int run(Scheme_Env *e, int argc, char *argv[])
{
Scheme_Object *curout = NULL, *v = NULL, *a[2] = {NULL, NULL};
Scheme_Config *config = NULL;
int i;
mz_jmp_buf * volatile save = NULL, fresh;
MZ_GC_DECL_REG(8);
MZ_GC_VAR_IN_REG(0, e);
MZ_GC_VAR_IN_REG(1, curout);
MZ_GC_VAR_IN_REG(2, save);
MZ_GC_VAR_IN_REG(3, config);
MZ_GC_VAR_IN_REG(4, v);
MZ_GC_ARRAY_VAR_IN_REG(5, a, 2);
MZ_GC_REG();
declare_modules(e);
v = scheme_intern_symbol("racket/base");
scheme_namespace_require(v);
config = scheme_current_config();
curout = scheme_get_param(config, MZCONFIG_OUTPUT_PORT);
save = scheme_current_thread->error_buf;
scheme_current_thread->error_buf = &fresh;
if (scheme_setjmp(scheme_error_buf)) {
scheme_current_thread->error_buf = save;
return -1; /* There was an error */
} else {
/* read-eval-print loop, uses initial Scheme_Env: */
a[0] = scheme_intern_symbol("racket/base");
a[1] = scheme_intern_symbol("read-eval-print-loop");
v = scheme_dynamic_require(2, a);
scheme_apply(v, 0, NULL);
scheme_current_thread->error_buf = save;
}
MZ_GC_UNREG();
return 0;
}
int main(int argc, char *argv[])
{
return scheme_main_setup(1, run, argc, argv);
}
不起作用的事情(及其错误信息):
从REPL调用(hw)
hw: undefined:
cannot reference undefined identifier
context...:
/usr/local/share/racket/collects/racket/private/misc.rkt:87:7
((dynamic-require 'hw 'hw))
standard-module-name-resolver: collection not found
for module path: hw
collection: "hw"
in collection directories:
context...:
show-collection-err
standard-module-name-resolver
/usr/local/share/racket/collects/racket/private/misc.rkt:87:7
((dynamic-require "hw.rkt" 'hw))
standard-module-name-resolver: collection not found
for module path: racket/base/lang/reader
collection: "racket/base/lang"
in collection directories:
context...:
show-collection-err
standard-module-name-resolver
standard-module-name-resolver
/usr/local/share/racket/collects/racket/private/misc.rkt:87:7
编辑示例代码
v = scheme_intern_symbol("racket/base");
scheme_namespace_require(v);
v = scheme_intern_symbol("hw");
scheme_namespace_require(v);
错误:
standard-module-name-resolver: collection not found
for module path: hw
collection: "hw"
in collection directories:
context...:
show-collection-err
standard-module-name-resolver
SIGSEGV MAPERR sicode 1 fault on addr 0xd0
Aborted
(段错误可能是因为我在尝试scheme_namespace_require
之前没有检查' v'的价值。)
编辑示例代码mk。 2
v = scheme_intern_symbol("racket/base");
scheme_namespace_require(v);
v = scheme_intern_symbol("hw.rkt");
scheme_namespace_require(v);
错误:
hw.rkt: bad module path
in: hw.rkt
context...:
standard-module-name-resolver
SIGSEGV MAPERR sicode 1 fault on addr 0xd0
Aborted
(re:segfault:如上所述)
编辑示例代码mk。 3
v = scheme_intern_symbol("racket/base");
scheme_namespace_require(v);
v = scheme_intern_symbol("./hw.rkt");
scheme_namespace_require(v);
(如上所述)
编辑示例代码mk。 4
/* read-eval-print-loop, uses initial Scheme_Env: */
a[0] = scheme_intern_symbol("hw");
a[1] = scheme_intern_symbol("hw");
v = scheme_dynamic_require(2, a);
(如mk.1,保存段错误)
编辑示例代码mk。 5
/* read-eval-print loop, uses initial Scheme_Env: */
a[0] = scheme_intern_symbol("hw");
a[1] = scheme_eval(a[0], e);
scheme_apply(a[1], 0, NULL);
错误:
hw: undefined;
cannot reference undefined identifier