Add self reference in closures without having to use vars.

README.md

@@ -27,31 +27,17 @@ Byte code interpreter with an assembly interface
 Proper tail calls for functional code
 Direct interop with C
 
-
-
 ## Compiling and Running
 
-Clone the repository and run:
+To build the runtime and run test, run
 ```sh
-make run
-```
-To build the runtime and launch a repl.
-
-## Basic programs
-
-To run some basic programs, run the client with one argument, the name of the
-file to run. For example, the client that is built will be located in the
-client directory, so running a program `script.dst` from the project directory
-would be
-```bash
-client/dst script.dst
+make test
 ```
 
-You can also use the `--help` option to see more usage information for the vm.
-
-## Running Tests
-
-Simply run `make test` to run the currently minimal test suite.
+A repl can also be run with
+```sh
+make repl
+```
 
 ## Todo
 

core/compile.c

@@ -150,6 +150,7 @@ void dstc_scope(DstCompiler *c, int flags) {
     scope.defs = NULL;
     scope.slots = NULL;
     scope.smax = -1;
+    scope.selfconst = -1;
     scope.bytecode_start = dst_v_count(c->buffer);
     scope.flags = flags;
 
@@ -224,7 +225,6 @@ DstSlot dstc_resolve(
         for (i = 0; i < len; i++) {
             if (scope->syms[i].sym == sym) {
                 ret = scope->syms[i].slot;
-                ret.flags |= DST_SLOT_NAMED;
                 goto found;
             }
         }

core/compile.h

@@ -91,6 +91,9 @@ struct DstScope {
      * that corresponds to the direct parent's stack will always have value 0. */
     int32_t *envs;
 
+    /* Where to add reference to self in constants */
+    int32_t selfconst;
+
     int32_t bytecode_start;
     int flags;
 };

core/compile_specials.c

@@ -416,6 +416,7 @@ DstSlot dstc_fn(DstFopts opts, DstAst *ast, int32_t argn, const Dst *argv) {
     DstFopts subopts = dstc_fopts_default(c);
     const Dst *params;
     int varargs = 0;
+    int selfref = 0;
 
     if (argn < 2) {
         dstc_cerror(c, ast, "expected at least 2 arguments to function literal");
@@ -428,8 +429,11 @@ DstSlot dstc_fn(DstFopts opts, DstAst *ast, int32_t argn, const Dst *argv) {
     /* Read function parameters */
     parami = 0;
     arity = 0;
-    head = dst_ast_unwrap(argv[0]);
-    if (dst_checktype(head, DST_SYMBOL)) parami = 1;
+    head = dst_ast_unwrap1(argv[0]);
+    if (dst_checktype(head, DST_SYMBOL)) {
+        selfref = 1;
+        parami = 1;
+    }
     if (parami >= argn) {
         dstc_cerror(c, dst_ast_node(argv[0]), "expected function parameters");
         return dstc_cslot(dst_wrap_nil());
@@ -438,7 +442,7 @@ DstSlot dstc_fn(DstFopts opts, DstAst *ast, int32_t argn, const Dst *argv) {
     if (dst_seq_view(paramv, &params, &paramcount)) {
         int32_t i;
         for (i = 0; i < paramcount; i++) {
-            Dst param = dst_ast_unwrap(params[i]);
+            Dst param = dst_ast_unwrap1(params[i]);
             if (dst_checktype(param, DST_SYMBOL)) {
                 DstSlot slot;
                 /* Check for varargs */
@@ -467,6 +471,17 @@ DstSlot dstc_fn(DstFopts opts, DstAst *ast, int32_t argn, const Dst *argv) {
         return dstc_cslot(dst_wrap_nil());
     }
 
+    /* Check for self ref */
+    if (selfref) {
+        DstSlot slot;
+        slot.envindex = 0;
+        slot.flags = DST_SLOT_NAMED | DST_FUNCTION;
+        slot.constant = dst_wrap_nil();
+        slot.index = dstc_lsloti(c);
+        dstc_emit(c, ast, (slot.index << 8) | DOP_LOAD_SELF);
+        dstc_nameslot(c, dst_unwrap_symbol(head), slot);
+    }
+
     /* Compile function body */
     for (argi = parami + 1; argi < argn; argi++) {
         DstSlot s;

core/opcodes.h

@@ -69,8 +69,8 @@ enum DstOpCode {
     DOP_LOAD_FALSE,
     DOP_LOAD_INTEGER,
     DOP_LOAD_CONSTANT,
-    DOP_LOAD_SELF,
     DOP_LOAD_UPVALUE,
+    DOP_LOAD_SELF,
     DOP_SET_UPVALUE,
     DOP_CLOSURE,
     DOP_PUSH,