From 1d496f5f7f01b20fb34e63d1c85a33d8decd1894 Mon Sep 17 00:00:00 2001
From: ubq323 <ubq323@ubq323.website>
Date: Sat, 22 Jun 2024 12:23:55 +0100
Subject: add function literals

---
 chunk.h | 25 +++++++++++++++++++++++++
 com.c   | 44 +++++++++++++++++++++++++++++++++++++-------
 com.h   | 18 ++++++++++++++++++
 dis.c   | 11 +++++++++++
 val.c   |  6 ++++++
 val.h   |  1 +
 6 files changed, 98 insertions(+), 7 deletions(-)
 create mode 100644 chunk.h
 create mode 100644 com.h

diff --git a/chunk.h b/chunk.h
new file mode 100644
index 0000000..afefda0
--- /dev/null
+++ b/chunk.h
@@ -0,0 +1,25 @@
+#ifndef _chunk_h
+#define _chunk_h
+
+typedef struct _chunk Chunk;
+typedef struct _compiler Compiler;
+typedef struct _state State;
+
+
+struct _chunk {
+	struct { 
+		size_t len;
+		size_t cap;
+		uint8_t *d;
+	} bc;
+	struct {
+		size_t len;
+		size_t cap;
+		Val *d;
+	} consts;
+};
+Chunk chunk_new(State *S);
+size_t chunk_wbc(Compiler *C, uint8_t byte);
+size_t chunk_wconst(Compiler *C, Val v);
+
+#endif
diff --git a/com.c b/com.c
index 4f377ce..92f0d80 100644
--- a/com.c
+++ b/com.c
@@ -27,7 +27,16 @@ Chunk chunk_new(State *S) {
 	return (Chunk){ 0 };
 }
 
+Compiler compiler_new(Compiler *outer, Chunk *ch) {
+	return (Compiler){
+		.S = outer->S,
+		.ch = ch,
+	};
+}
+
+
 size_t chunk_wbc(Compiler *C, uint8_t byte) {
+	printf("\t%p %hd\n",C, byte);
 	Chunk *ch = C->ch;
 	if (ch->bc.len == ch->bc.cap) {
 		size_t newsz = (ch->bc.cap == 0 ? 8 : ch->bc.cap * 2);
@@ -76,7 +85,7 @@ void single_form(Compiler *C, AstVec l, Op op) {
 	chunk_wbc(C, op);
 }
 
-void set_form(Compiler *C, AstVec l, Op op) {
+void set_form(Compiler *C, AstVec l, Op _) {
 	AstNode ident = l.vals[1];
 	if (ident.ty != AST_IDENT) {
 		fprintf(stderr, "set's first argument must be identifier");
@@ -88,7 +97,7 @@ void set_form(Compiler *C, AstVec l, Op op) {
 	chunk_wbc(C, chunk_wconst(C, VAL_OBJ(o)));
 }
 
-void do_form(Compiler *C, AstVec l, Op op) {
+void do_form(Compiler *C, AstVec l, Op _) {
 	for (int i = 1; i < l.len - 1; i++) {
 		compile_node(C, l.vals[i]);
 		chunk_wbc(C, OP_DROP);
@@ -96,7 +105,7 @@ void do_form(Compiler *C, AstVec l, Op op) {
 	compile_node(C, l.vals[l.len - 1]);
 }
 
-void if_form(Compiler *C, AstVec l, Op op) {
+void if_form(Compiler *C, AstVec l, Op _) {
 	// (if cond if-true if-false)
 	// cond
 	// 0branch ->A
@@ -118,7 +127,7 @@ void if_form(Compiler *C, AstVec l, Op op) {
 	patch(C, ph_b, dest_b - ph_b - 2);
 }
 
-void while_form(Compiler *C, AstVec l, Op op) {
+void while_form(Compiler *C, AstVec l, Op _) {
 	// (while cond body ...)
 	// A:
 	// cond
@@ -150,9 +159,29 @@ void arith_form(Compiler *C, AstVec l, Op op) {
 	chunk_wbc(C, op);
 }
 
-// void fn_form(Compiler *C, AstVec l, Op op) {
-// 	Compiler subcompiler = compiler_new(C);
-	
+void fn_form(Compiler *C, AstVec l, Op op) {
+	// (fn (arg arg arg) body ...)
+	if (l.vals[1].ty != AST_LIST) {
+		fprintf(stderr, "fn's first argument must be list");
+		exit(1);
+	}
+	AstVec arglist = l.vals[1].as.list;
+
+	ObjFunc *func = objfunc_new(C->S);
+	Compiler subcompiler = compiler_new(C, &func->chunk);
+
+	for (int i = 2; i < l.len - 1; i++) {
+		compile_node(&subcompiler, l.vals[i]);
+		chunk_wbc(&subcompiler, OP_DROP);
+	}
+	compile_node(&subcompiler, l.vals[l.len-1]);
+	chunk_wbc(&subcompiler, OP_RET);
+
+	chunk_wbc(C, OP_LOADK);
+	chunk_wbc(C, chunk_wconst(C, VAL_OBJ(func)));
+}
+
+
 
 static BuiltinForm builtin_forms[] = {
 	{ "puts",  1, false, single_form, OP_PUTS },
@@ -161,6 +190,7 @@ static BuiltinForm builtin_forms[] = {
 	{ "do",    1,  true, do_form, 0 },
 	{ "if",    3, false, if_form, 0 },
 	{ "while", 2,  true, while_form, 0 },
+	{ "fn",    2,  true, fn_form, 0 },
 #define ARITH_OP(str, op) \
 	{ str, 2, false, arith_form, op },
 	ARITH_OP("+", OP_ADD)
diff --git a/com.h b/com.h
new file mode 100644
index 0000000..f08769e
--- /dev/null
+++ b/com.h
@@ -0,0 +1,18 @@
+#ifndef _com_h
+#define _com_h
+
+typedef struct _compiler Compiler;
+
+#include "state.h"
+#include "chunk.h"
+
+
+struct _compiler {
+	State *S;
+	Chunk *ch;
+};
+Compiler compiler_new(Compiler *outer, Chunk *ch);
+
+#define BYTECODE(C) (C->ch->bc)
+
+#endif
diff --git a/dis.c b/dis.c
index ba0e1db..5097b05 100644
--- a/dis.c
+++ b/dis.c
@@ -87,6 +87,17 @@ void disasm_chunk(Chunk *ch) {
 
 		}
 	}
+	printf("\n");
+
+	for (uint8_t cix = 0; cix < ch->consts.len; cix++) {
+		Val c = ch->consts.d[cix];
+		if (IS_FUNC(c)) {
+			printf("const %d is function:\n", cix);
+			disasm_chunk(&AS_FUNC(c)->chunk);
+		}
+	}
+
+
 }
 
 
diff --git a/val.c b/val.c
index ec3e636..621b073 100644
--- a/val.c
+++ b/val.c
@@ -47,6 +47,12 @@ static ObjString *objstring_create(State *S, char *src, size_t len, uint32_t has
 	return o;
 }
 
+ObjFunc *objfunc_new(State *S) {
+	ObjFunc *o = NEW_OBJ(S, ObjFunc, OTY_FUNC);
+	o->chunk = chunk_new(S);
+	return o;
+}
+
 
 void print_val(Val v) {
 	switch (v.ty) {
diff --git a/val.h b/val.h
index e4227a4..c71e419 100644
--- a/val.h
+++ b/val.h
@@ -72,6 +72,7 @@ ObjFunc *objfunc_new(State *S);
 #define IS_OBJ(x) (x.ty == TY_OBJ)
 
 #define IS_STRING(x) (is_obj_ty((x), OTY_STRING))
+#define IS_FUNC(x) (is_obj_ty((x), OTY_FUNC))
 
 #define AS_NUM(x) (x.as.d)
 #define AS_BOOL(x) (x.as.b)
-- 
cgit v1.2.3