Add len() operator

WL.c

@@ -351,6 +351,7 @@ typedef enum {
     NODE_INCLUDE,
     NODE_SELECT,
     NODE_NESTED,
+    NODE_OPER_LEN,
     NODE_OPER_POS,
     NODE_OPER_NEG,
     NODE_OPER_ASS,
@@ -459,6 +460,7 @@ typedef enum {
     TOKEN_KWORD_TRUE,
     TOKEN_KWORD_FALSE,
     TOKEN_KWORD_INCLUDE,
+    TOKEN_KWORD_LEN,
     TOKEN_VALUE_FLOAT,
     TOKEN_VALUE_INT,
     TOKEN_VALUE_STR,
@@ -550,6 +552,7 @@ String tok2str(Token token, char *buf, int max)
         case TOKEN_KWORD_TRUE: return S("true");
         case TOKEN_KWORD_FALSE: return S("false");
         case TOKEN_KWORD_INCLUDE: return S("include");
+        case TOKEN_KWORD_LEN: return S("len");
 
         case TOKEN_VALUE_FLOAT:
         {
@@ -688,6 +691,7 @@ Token next_token(Parser *p)
         if (streq(kword, S("true")))    return (Token) { .type=TOKEN_KWORD_TRUE    };
         if (streq(kword, S("false")))   return (Token) { .type=TOKEN_KWORD_FALSE   };
         if (streq(kword, S("include"))) return (Token) { .type=TOKEN_KWORD_INCLUDE };
+        if (streq(kword, S("len")))     return (Token) { .type=TOKEN_KWORD_LEN     };
 
         return (Token) { .type=TOKEN_IDENT, .sval=kword };
     }
@@ -1249,6 +1253,23 @@ Node *parse_atom(Parser *p)
         }
         break;
 
+        case TOKEN_KWORD_LEN:
+        {
+            Node *child = parse_atom(p);
+            if (child == NULL)
+                return NULL;
+
+            Node *parent = alloc_node(p);
+            if (parent == NULL)
+                return NULL;
+
+            parent->type = NODE_OPER_LEN;
+            parent->left = child;
+
+            ret = parent;
+        }
+        break;
+
         case TOKEN_IDENT:
         {
             Node *node = alloc_node(p);
@@ -2046,6 +2067,12 @@ void print_node(Node *node)
         }
         break;
 
+        case NODE_OPER_LEN:
+        printf("len(");
+        print_node(node->left);
+        printf(")");
+        break;
+
         case NODE_OPER_POS:
         printf("(");
         printf("+");
@@ -2420,6 +2447,7 @@ enum {
     OPCODE_FOR     = 0x2E,
     OPCODE_PUSHT   = 0x2F,
     OPCODE_PUSHFL  = 0x30,
+    OPCODE_LEN     = 0x31,
 };
 
 typedef struct {
@@ -2757,6 +2785,7 @@ bool is_expr(Node *node)
         case NODE_SELECT:
         case NODE_NESTED:
         case NODE_FUNC_CALL:
+        case NODE_OPER_LEN:
         case NODE_OPER_POS:
         case NODE_OPER_NEG:
         case NODE_OPER_ASS:
@@ -3002,6 +3031,20 @@ void assemble_expr(Assembler *a, Node *node, int num_results)
         }
         break;
 
+        case NODE_OPER_LEN:
+        assemble_expr(a, node->left, 1);
+        append_u8(&a->out, OPCODE_LEN);
+
+        if (num_results == 0)
+            append_u8(&a->out, OPCODE_POP);
+        else if (num_results != -1 && num_results != 1) {
+            append_u8(&a->out, OPCODE_GROUP);
+            append_u8(&a->out, OPCODE_GTRUNC);
+            append_u32(&a->out, num_results-1);
+            append_u8(&a->out, OPCODE_GCOALESCE);
+        }
+        break;
+
         case NODE_OPER_POS:
         assemble_expr(a, node->left, num_results);
         break;
@@ -5526,8 +5569,6 @@ int step(WL_State *state)
             uint8_t  var_2 = read_u8(state);
             uint32_t end   = read_u32(state);
 
-            printf("for end %u\n", end); // TODO
-
             int base;
             {
                 int group = state->frames[state->num_frames-1].group;
@@ -5576,6 +5617,24 @@ int step(WL_State *state)
         }
         break;
 
+        case OPCODE_LEN:
+        {
+            Value set = state->eval_stack[state->eval_depth-1];
+
+            Type type = type_of(set);
+            if (type != TYPE_ARRAY && type != TYPE_MAP) {
+                assert(0); // TODO
+            }
+
+            Value len = make_int(state->a, value_length(set));
+            if (len == VALUE_ERROR) {
+                assert(0); // TODO
+            }
+
+            state->eval_stack[state->eval_depth++] = len;
+        }
+        break;
+
         default:
         eval_report(state, "Invalid opcode (offset %d)", state->off-1);
         return -1;

src/assemble.c

@@ -317,6 +317,7 @@ bool is_expr(Node *node)
         case NODE_SELECT:
         case NODE_NESTED:
         case NODE_FUNC_CALL:
+        case NODE_OPER_LEN:
         case NODE_OPER_POS:
         case NODE_OPER_NEG:
         case NODE_OPER_ASS:
@@ -562,6 +563,20 @@ void assemble_expr(Assembler *a, Node *node, int num_results)
         }
         break;
 
+        case NODE_OPER_LEN:
+        assemble_expr(a, node->left, 1);
+        append_u8(&a->out, OPCODE_LEN);
+
+        if (num_results == 0)
+            append_u8(&a->out, OPCODE_POP);
+        else if (num_results != -1 && num_results != 1) {
+            append_u8(&a->out, OPCODE_GROUP);
+            append_u8(&a->out, OPCODE_GTRUNC);
+            append_u32(&a->out, num_results-1);
+            append_u8(&a->out, OPCODE_GCOALESCE);
+        }
+        break;
+
         case NODE_OPER_POS:
         assemble_expr(a, node->left, num_results);
         break;

src/assemble.h

@@ -49,6 +49,7 @@ enum {
     OPCODE_FOR     = 0x2E,
     OPCODE_PUSHT   = 0x2F,
     OPCODE_PUSHFL  = 0x30,
+    OPCODE_LEN     = 0x31,
 };
 
 typedef struct {

src/eval.c

@@ -934,6 +934,24 @@ int step(WL_State *state)
         }
         break;
 
+        case OPCODE_LEN:
+        {
+            Value set = state->eval_stack[state->eval_depth-1];
+
+            Type type = type_of(set);
+            if (type != TYPE_ARRAY && type != TYPE_MAP) {
+                assert(0); // TODO
+            }
+
+            Value len = make_int(state->a, value_length(set));
+            if (len == VALUE_ERROR) {
+                assert(0); // TODO
+            }
+
+            state->eval_stack[state->eval_depth++] = len;
+        }
+        break;
+
         default:
         eval_report(state, "Invalid opcode (offset %d)", state->off-1);
         return -1;

src/parse.c

@@ -25,6 +25,7 @@ typedef enum {
     TOKEN_KWORD_TRUE,
     TOKEN_KWORD_FALSE,
     TOKEN_KWORD_INCLUDE,
+    TOKEN_KWORD_LEN,
     TOKEN_VALUE_FLOAT,
     TOKEN_VALUE_INT,
     TOKEN_VALUE_STR,
@@ -116,6 +117,7 @@ String tok2str(Token token, char *buf, int max)
         case TOKEN_KWORD_TRUE: return S("true");
         case TOKEN_KWORD_FALSE: return S("false");
         case TOKEN_KWORD_INCLUDE: return S("include");
+        case TOKEN_KWORD_LEN: return S("len");
 
         case TOKEN_VALUE_FLOAT:
         {
@@ -254,6 +256,7 @@ Token next_token(Parser *p)
         if (streq(kword, S("true")))    return (Token) { .type=TOKEN_KWORD_TRUE    };
         if (streq(kword, S("false")))   return (Token) { .type=TOKEN_KWORD_FALSE   };
         if (streq(kword, S("include"))) return (Token) { .type=TOKEN_KWORD_INCLUDE };
+        if (streq(kword, S("len")))     return (Token) { .type=TOKEN_KWORD_LEN     };
 
         return (Token) { .type=TOKEN_IDENT, .sval=kword };
     }
@@ -815,6 +818,23 @@ Node *parse_atom(Parser *p)
         }
         break;
 
+        case TOKEN_KWORD_LEN:
+        {
+            Node *child = parse_atom(p);
+            if (child == NULL)
+                return NULL;
+
+            Node *parent = alloc_node(p);
+            if (parent == NULL)
+                return NULL;
+
+            parent->type = NODE_OPER_LEN;
+            parent->left = child;
+
+            ret = parent;
+        }
+        break;
+
         case TOKEN_IDENT:
         {
             Node *node = alloc_node(p);
@@ -1612,6 +1632,12 @@ void print_node(Node *node)
         }
         break;
 
+        case NODE_OPER_LEN:
+        printf("len(");
+        print_node(node->left);
+        printf(")");
+        break;
+
         case NODE_OPER_POS:
         printf("(");
         printf("+");

src/parse.h

@@ -20,6 +20,7 @@ typedef enum {
     NODE_INCLUDE,
     NODE_SELECT,
     NODE_NESTED,
+    NODE_OPER_LEN,
     NODE_OPER_POS,
     NODE_OPER_NEG,
     NODE_OPER_ASS,