CImport

One of the rudimentary ways for extending Senegal is by defining new C function.

While this doesn't allow you to call any c function, Senegal exposes c functions to define functions/variables for senegal within core/sapi.c. When you build senegal with CMake, it generates a shared library and copies it to the bin folder which can be used to access necessary files.

Example

Here's a very general example to help you get the gist of it.

We first create a new c file. Lets call it addNums.c.

// Correct these paths as needed

#include 'svm.h'

#include 'sapi.h'

// This is the actual implementation of addNums.

Constant addNums(VM* vm, int arity, Constant* args) {

// Expects a number of arguments to be passed.

expect(2, arity, "addNums");

// The first given argument is at args[0].

// If this was to be a class method, the class instance would be at args[-1].

double a = AS_NUMBER(args[0]);

double b = AS_NUMBER(args[1]);

return NUM_CONST(a + b);

}

// When senegal encounters a `cimport`, it searches for a `initLib` symbol within the library.

// This function will always have the same structure.

Constant initLib(VM* vm, int arity, Constant* args) {

// defineGlobalFunc is imported from sapi.h.

defineGlobalFunc(vm, "addNums", addNums);

return NULL_CONST;

}

Now generate a shared library from this. For simplicity's sake, we'll call it addNums.so.

To use this within senegal, import the library as such:

// This assumes that addNums.so is in the same directory as this file.

cimport 'addNums'

println(addNums(10, 5)); // Should print 15.

C API Commonly Used Functions

Function	Header	Description
expect()	core/includes/sapi.h	Checks to see if the correct number of arguments are given
defineGlobal()	core/includes/sapi.h	Defines a global variable
defineGlobalFunc()	core/includes/sapi.h	Defines a function
defineClassNativeStaticField()	core/includes/sapi.h	Defines a static field for a given class
defineClassNativeStaticMethod()	core/includes/sapi.h	Defines a static method for a given class
defineClassNativeField()	core/includes/sapi.h	Defines a field for a given class
defineClassNativeMethod()	core/includes/sapi.h	Defines a method for a given class
newClass	src/includes/svm.h	Creates a new Senegal Class
copyString	src/includes/sparser.h	Creates a new Senegal String

C API Commonly Used Macros

Macros	Header	Description
AS_NUMBER	src/includes/sconstant.h	Returns a Senegal constant as a C double
IS_NUMBER	src/includes/sconstant.h	Checks if Senegal constant is a Senegal num type
NUM_CONST	src/includes/sconstant.h	Returns a C double as a Senegal constant
IS_NULL	src/includes/sconstant.h	Checks if Senegal constant is a Senegal null const
NULL_CONST	src/includes/sconstant.h	Returns a Senegal null const
AS_BOOL	src/includes/sconstant.h	Returns a Senegal constant as a Senegal Bool
IS_BOOL	src/includes/sconstant.h	Checks if Senegal constant is a Senegal Bool
BOOL_CONST	src/includes/sconstant.h	Creates a new Senegal bool from a c boolean literal
AS_STRING	src/includes/sconstant.h	Returns a Senegal constant as a Senegal String
IS_STRING	src/includes/sconstant.h	Checks if Senegal constant is a Senegal String
AS_CLASS	src/includes/svm.h	Returns a Senegal constant as a Senegal Class
IS_CLASS	src/includes/svm.h	Checks if Senegal constant is a Senegal Class
AS_CLOSURE	src/includes/svm.h	Returns a Senegal constant as a Senegal closure
IS_CLOSURE	src/includes/svm.h	Checks if Senegal constant is a Senegal closure
AS_LIST	src/includes/svm.h	Returns a Senegal constant as a Senegal List
IS_LIST	src/includes/svm.h	Checks if Senegal constant is a Senegal List
AS_MAP	src/includes/svm.h	Returns a Senegal constant as a Senegal Map
IS_MAP	src/includes/svm.h	Checks if Senegal constant is a Senegal Map