add standard functions: write/newline

Makefile

@@ -4,7 +4,7 @@ build:
 	cd src; \
 	yacc -d parse.y; \
 	lex scan.l
-	gcc -o bin/picrin -I./include src/main.c src/state.c src/gc.c src/pair.c src/write.c src/symbol.c src/value.c src/y.tab.c src/lex.yy.c src/eval.c src/bool.c src/vm.c
+	gcc -o bin/picrin -I./include src/main.c src/state.c src/gc.c src/pair.c src/port.c src/symbol.c src/value.c src/y.tab.c src/lex.yy.c src/eval.c src/bool.c src/vm.c src/init.c
 
 clean:
 	rm -f src/y.tab.c src/y.tab.h src/lex.yy.c

src/init.c

@@ -0,0 +1,14 @@
+#include "picrin.h"
+
+void pic_init_port(pic_state *);
+
+#define DONE pic_gc_arena_restore(pic, ai);
+
+void
+pic_init_core(pic_state *pic)
+{
+  int ai;
+
+  ai = pic_gc_arena_preserve(pic);
+  pic_init_port(pic); DONE;
+}

src/port.c

@@ -22,7 +22,7 @@ pic_debug(pic_state *pic, pic_value obj)
     printf("%s", pic_symbol_ptr(obj)->name);
     break;
   case PIC_TT_FLOAT:
-    printf("%f", pic_float(obj));
+    printf("%g", pic_float(obj));
     break;
   case PIC_TT_UNDEF:
     printf("#<undef>");
@@ -35,3 +35,28 @@ pic_debug(pic_state *pic, pic_value obj)
     break;
   }
 }
+
+static pic_value
+pic_port_write(pic_state *pic)
+{
+  pic_value v;
+
+  pic_get_args(pic, "o", &v);
+  pic_debug(pic, v);
+  return pic_undef_value();
+}
+
+static pic_value
+pic_port_newline(pic_state *pic)
+{
+  puts("");
+  return pic_undef_value();
+}
+
+void
+pic_init_port(pic_state *pic)
+{
+  pic_defun(pic, "write", pic_port_write);
+  pic_defun(pic, "newline", pic_port_newline);
+}
+

src/state.c

@@ -15,6 +15,8 @@ pic_new_empty_env()
   return env;
 }
 
+void pic_init_core(pic_state *);
+
 pic_state *
 pic_open()
 {
@@ -34,11 +36,14 @@ pic_open()
   /* GC arena */
   pic->arena_idx = 0;
 
-  pic->global_env = pic_new_empty_env();
   pic->sDEFINE = pic_intern_cstr(pic, "define");
   pic->sCONS = pic_intern_cstr(pic, "cons");
   pic->sADD = pic_intern_cstr(pic, "add");
 
+  /* global environment */
+  pic->global_env = pic_new_empty_env();
+  pic_init_core(pic);
+
   return pic;
 }