add support for statement lists (so that e.g. conditionals and function bodies can be defined)

lapis.c

@@ -5,6 +5,13 @@
 #include <stdbool.h>
 #include <string.h>
 
+struct lapis_node_s;
+
+typedef struct {
+    size_t nnodes;
+    struct lapis_node_s *nodes;
+} lapis_stmt_t;
+
 typedef struct {
     enum lapis_ttype {
         LAPIS_TTYPE_NONE,
@@ -14,9 +21,14 @@ typedef struct {
         LAPIS_TTYPE_INT,
         LAPIS_TTYPE_BOOL,
         LAPIS_TTYPE_OPER,
+        LAPIS_TTYPE_STMT_LIST,
     } type;
 
     union {
+        struct {
+            size_t nstmts;
+            lapis_stmt_t *stmts;
+        };
         struct {
             size_t len;
             char * str;
@@ -54,6 +66,13 @@ void lapis_node_print(const lapis_node_t *nodes, size_t idx) {
         case LAPIS_TTYPE_INT:
             printf("%ld", nodes[idx].value.i64);
             break;
+        case LAPIS_TTYPE_STMT_LIST:
+            for (size_t n=0; n < nodes[idx].value.nstmts; n++) {
+                lapis_node_print(nodes[idx].value.stmts[n].nodes, nodes[idx].value.stmts[n].nnodes-1);
+                fputs("; ", stdout);
+            }
+            fputs("} ", stdout);
+            break;
     }
 
     if ( nodes[idx].rhs_idx != SIZE_MAX ) {
@@ -82,6 +101,8 @@ void lapis_token_free(lapis_token_t *token) {
     }
 }
 
+lapis_node_t *lapis_parse_expr(size_t *nnodes, FILE *f);
+
 lapis_token_t *lapis_parse_tokens(size_t *ntokens, FILE *f) {
 
     size_t num_tokens = 0;
@@ -91,7 +112,62 @@ lapis_token_t *lapis_parse_tokens(size_t *ntokens, FILE *f) {
     _Bool end_of_expression = false;
 
     int c;
-    while ( (c = fgetc(f)) != EOF && !end_of_expression ) {
+    while ( !end_of_expression && ((c = fgetc(f)) != EOF) ) {
+
+        if ( c == '{' ) {
+
+            size_t nstmts = 0;
+            lapis_stmt_t *stmts = NULL;
+
+            while (1) {
+
+                //puts("++++++++++");
+                size_t nnodes;
+                lapis_node_t *nodes = lapis_parse_expr(&nnodes, f);
+                //puts("----------");
+
+                if ( nodes == 0 ) break;
+
+                //printf("%lu: ", nstmts);
+                //lapis_node_print(nodes, nnodes-1);
+                //putchar('\n');
+
+                nstmts++;
+                stmts = realloc(stmts, nstmts * sizeof(lapis_stmt_t));
+
+                if ( stmts == NULL ) {
+                    fprintf(stderr, "ERROR[%d]: realloc failed!\n", __LINE__);
+                    goto ERROR;
+                }
+
+                stmts[nstmts-1] = (lapis_stmt_t) { .nnodes = nnodes, .nodes = nodes };
+            }
+
+            if ( nstmts > 0 ) {
+
+                tokens = realloc(tokens, (num_tokens + 2) * sizeof(lapis_token_t));
+                if ( tokens == NULL ) {
+                    fprintf(stderr, "ERROR [%s:%d]: realloc failed!\n", __func__, __LINE__);
+                    goto ERROR;
+                }
+
+                // need an operator to connect the statement list to the outer statement
+                tokens[num_tokens].type = LAPIS_TTYPE_OPER;
+                tokens[num_tokens].str = strdup("{");
+                tokens[num_tokens].len = 1;
+
+                num_tokens++;
+
+                // need an operator to connect the statement list to the outer statement
+                tokens[num_tokens].type = LAPIS_TTYPE_STMT_LIST;
+                tokens[num_tokens].stmts = stmts;
+                tokens[num_tokens].nstmts = nstmts;
+
+                num_tokens++;
+            }
+
+            c = ' ';
+        }
 
         _Bool in_escape = false;
 
@@ -108,9 +184,9 @@ lapis_token_t *lapis_parse_tokens(size_t *ntokens, FILE *f) {
             if ( c == EOF ) break;
         }
 
-        if ( c == ';' || (!in_escape && c == '\n') ) {
+        if ( c == ';' || c == '}' || (!in_escape && c == '\n') ) {
+            if ( num_tokens || c == '}' ) end_of_expression = true;
             c = ' ';
-            if ( num_tokens ) end_of_expression = true;
         }
 
         enum lapis_ttype cur_ttype;
@@ -290,6 +366,7 @@ lapis_node_t *lapis_parse_expr(size_t *nnodes, FILE *f) {
                 fputs("'\n", stderr);
                 goto ERROR;
             case 1ul*',':
+            case 1ul*'{':
                 oper_priorities[n] = 1;
                 oper_arg_form[n] = 3;
                 break;