first stub of handling primitive functions

interpreter/compile.bat

-g++ -Wno-write-strings -Wno-pointer-arith main.c desc.c mem.c parse.c -o main
+g++ -Wno-write-strings -Wno-pointer-arith main.c desc.c mem.c parse.c prim.c -o main

interpreter/desc.c

@@ -43,6 +43,17 @@ FunEntry* alloc_prim(char* name)
 	return entry;
 }
 
+void gen_slices(void* dest, void* forward_ptr, int arity)
+{
+	for(int i=0; i<arity; i++)
+	{
+		SliceEntry* slice = (SliceEntry*) dest + sizeof(SliceEntry) * i;
+		slice->flags.type = FT_SLICE;
+		slice->flags.arity = i;
+		slice->forward_ptr = forward_ptr;
+	}
+}
+
 void init_desc()
 {
 	__INT__ = alloc_prim("INT");

interpreter/desc.h

@@ -7,6 +7,7 @@
 #define FT_CAF_REDUCED 		4
 #define FT_FUN				5
 #define FT_SLICE			6
+#define FT_PRIM				7
 
 struct FunFlags
 {
@@ -58,6 +59,16 @@ struct RecordEntry
 	char name[];	
 };
 
+struct PrimEntry
+{
+	struct FunFlags flags;
+	int strictness;
+	void (*exec)();	
+	char name[];
+};
+
+void gen_slices(void* dest, void* forward_ptr, int arity);
+
 void init_desc();
 
 void add_desc(char* fn, FunFlags* desc);

interpreter/main.c

@@ -4,12 +4,14 @@
 
 #include "mem.h"
 #include "desc.h"
+#include "prim.h"
 #include "parse.h"
 
 int main()
 {   
 	init_mem();
 	init_desc();
+	init_prim();
 	
 	char* stream = "40 R10 example._R2 1 9 example.a9 example.b37 F12 example.g_482 3 AF3 add2 VA0 VA1 39 C9 example.fAF12 example.g_482 LI1 LI2 55 F13 example.Start0 0 AF10 example._R2 LI1 VF9 example.f29 F4 main0 0 VF13 example.Start";
 		 

interpreter/parse.c

@@ -48,17 +48,6 @@ void copyStringAndForward(char* dest, char** source, int length)
 	*source += length; 
 }
 
-void genSlices(void* dest, void* forward_ptr, int arity)
-{
-	for(int i=0; i<arity; i++)
-	{
-		SliceEntry* slice = (SliceEntry*) dest + sizeof(SliceEntry) * i;
-		slice->flags.type = FT_SLICE;
-		slice->flags.arity = i;
-		slice->forward_ptr = forward_ptr;
-	}
-}
-
 int parseDef1(char** ptr)
 {
 	int defSize;
@@ -106,7 +95,7 @@ int parseDef1(char** ptr)
 			entry->body = *ptr; 
 
 			// generate slices. avoid function call if arity is zero
-			if(arity>0) genSlices(entry_base, entry, arity);
+			if(arity>0) gen_slices(entry_base, entry, arity);
 			
 			add_desc(entry->name, (FunFlags*) entry);
 			break;
@@ -171,7 +160,7 @@ int parseDef1(char** ptr)
 				if(!parseInt(ptr, &entry->strictness)) return 0;
 				
 				// generate slices. avoid function call if arity is zero
-				if(arity>0) genSlices(entry_base, entry, arity);
+				if(arity>0) gen_slices(entry_base, entry, arity);
 				
 				add_desc(entry->name, (FunFlags*) entry);
 			}			
@@ -310,7 +299,7 @@ VarEntry* parseVar(char **ptr)
 			
 			copyStringAndForward(name, ptr, nameLength);
 			entry->f = (FunFlags*) find_desc(name); // can fail
-
+			
 			if(entry->f == 0)
 			{
 				printf("%s not found\n", name);

interpreter/prim.c

+
+#include <string.h>
+
+#include "prim.h"
+#include "desc.h"
+#include "mem.h"
+
+void __add()
+{
+	
+}
+
+PrimEntry* add_prim(int arity, int strictness, char* name, void (*exec)())
+{
+	int nameLength = strlen(name);
+	
+	// before the PrimEntry there are "arity" number of SliceEntries
+	void* entry_base = alloc_desc(sizeof(SliceEntry) * arity + sizeof(PrimEntry) + nameLength + 1);
+		
+	PrimEntry* entry = (PrimEntry*) (entry_base + sizeof(SliceEntry) * arity);
+	entry->flags.type = FT_PRIM;
+	entry->flags.arity = arity;
+	entry->strictness = strictness;
+	entry->exec = exec;
+	
+	// TODO: should it be copied at all?
+	memcpy(entry->name, name, nameLength);
+	entry->name[nameLength] = '\0';
+	
+	// generate slices. avoid function call if arity is zero
+	if(arity>0) gen_slices(entry_base, entry, arity);
+	
+	add_desc(entry->name, (FunFlags*) entry);
+}
+
+void init_prim()
+{
+	add_prim(2, 3, "add", &__add);
+}

interpreter/prim.h

+#ifndef __PRIM_H
+#define __PRIM_H
+
+void init_prim();
+
+#endif // __PRIM_H
\ No newline at end of file