Node:Init Snarfing with guile-snarf, Next:, Up:Snarfing

13.1.1 Init Snarfing with guile-snarf

When writing C code for use with Guile, you typically define a set of C functions, and then make some of them visible to the Scheme world by calling the scm_c_define_gsubr function; a C function published in this way is called a subr. If you have many subrs to publish, it can sometimes be annoying to keep the list of calls to scm_c_define_gsubr in sync with the list of function definitions. Frequently, a programmer will define a new subr in C, recompile the application, and then discover that the Scheme interpreter cannot see the subr, because of a missed call to scm_c_define_gsubr.

Guile provides the guile-snarf command to manage this problem. Using this tool, you can keep all the information needed to define the subr alongside the function definition itself; guile-snarf will extract this information from your source code, and automatically generate a file of calls to scm_c_define_gsubr which you can #include into an initialization function.