chickadee » chicken » foreign » foreign-lambda*

Similar to foreign-lambda, but instead of generating code to call an external function, the body of the C procedure is directly given in STRING ...:

(define my-strlen
  (foreign-lambda* int ((c-string str))
    "int n = 0;
     while(*(str++)) ++n;
     C_return(n);") )

(my-strlen "one two three")             ==> 13

For obscure technical reasons you should use the C_return macro instead of the normal return statement to return a result from the foreign lambda body as some cleanup code has to be run before execution commences in the calling code.