Introduce forlan functions.

* lib/forlan.c (forlan_find_function): New function.
(func_dump, func_print)
(func_error,func_parent): Function placeholders.
* lib/forlan.h (forlan_node_func) <fp>: Change datatype.
(forlan_eval_env_t): New typedef.
(forlan_value_type): New enum.
(forlan_value,forlan_function): New struct.
* lib/forlangrm.y: Check number of arguments passed to functions.
* tests/forlan01.at: Update.

3 files changed, 127 insertions, 4 deletions

diff --git a/lib/forlan.c b/lib/forlan.c
index 0854d08..008ee5b 100644
--- a/lib/forlan.c
+++ b/lib/forlan.c
@@ -85,7 +85,7 @@ void
 dump_func(FILE *fp, union forlan_node *p, int *num, int lev)
 {
 	struct grecs_list_entry *ep;
-	fprintf(fp, "CALL: %s\n", p->func.fp);
+	fprintf(fp, "CALL: %s\n", p->func.fp->name);
 	if (p->func.args)
 		for (ep = p->func.args->head; ep; ep = ep->next)
 			forlan_dump_node(fp, ep->data, num, lev + 1);
@@ -256,3 +256,53 @@ forlan_dump_tree(FILE *fp, union forlan_node *node)
 	int n = 0;
 	forlan_dump_node(fp, node, &n, 0);
 }
+
+struct forlan_eval_env {
+	struct grecs_node *tree;
+	struct grecs_node *last;
+};
+
+void
+func_dump(forlan_eval_env_t env, struct grecs_list *list)
+{
+	abort();
+}
+
+void
+func_print(forlan_eval_env_t env, struct grecs_list *list)
+{
+	abort();
+}
+
+void
+func_error(forlan_eval_env_t env, struct grecs_list *list)
+{
+	abort();
+}
+
+void
+func_parent(forlan_eval_env_t env, struct grecs_list *list)
+{
+	abort();
+}
+
+static struct forlan_function functab[] = {
+	{ "dump",   forlan_value_void, "n", 1, 1, func_dump },
+	{ "print",  forlan_value_void, "", 1, -1, func_print },
+	{ "error",  forlan_value_void, "", 1, -1, func_error },
+	{ "parent", forlan_value_node, "n", 1, 1, func_parent },
+	{ NULL }
+};
+
+struct forlan_function *
+forlan_find_function(const char *name)
+{
+	struct forlan_function *fp;
+	for (fp = functab; fp->name; fp++)
+		if (strcmp(name, fp->name) == 0)
+			return fp;
+	return NULL;
+}	
+
+
+
diff --git a/lib/forlan.h b/lib/forlan.h
index 4dadc70..aa4dbe4 100644
--- a/lib/forlan.h
+++ b/lib/forlan.h
@@ -58,7 +58,7 @@ struct forlan_node_test {
 /* Function call */
 struct forlan_node_func {
 	enum forlan_type type;
-	void *fp; /* FIXME: replace with typedef */
+	struct forlan_function *fp;
 	struct grecs_list *args; /* Arguments are struct forlan_node * */
 };
 
@@ -121,3 +121,30 @@ extern union forlan_node *forlan_parse_tree;
 
 void forlan_dump_node(FILE *fp, union forlan_node *p, int *num, int lev);
 void forlan_dump_tree(FILE *fp, union forlan_node *node);
+
+typedef struct forlan_eval_env *forlan_eval_env_t;
+
+enum forlan_value_type {
+	forlan_value_void,
+	forlan_value_node,
+	forlan_value_literal
+};
+
+struct forlan_value {
+	enum forlan_value_type type;
+	union {
+		char *string;
+		struct grecs_node *node;
+	} v;
+};
+
+struct forlan_function {
+	char *name;
+	enum forlan_value_type rettype;
+	char *argtypes;
+	int minargs;
+	int maxargs;
+	void (*func)(forlan_eval_env_t, struct grecs_list *list);
+};
+
+struct forlan_function *forlan_find_function(const char *name);
diff --git a/lib/forlangrm.y b/lib/forlangrm.y
index 1b7781d..d2e0489 100644
--- a/lib/forlangrm.y
+++ b/lib/forlangrm.y
@@ -137,6 +137,12 @@ node      : complist
 		    $$->comp.abs = 1;
 		    $$->comp.node = forlan_stmt_from_list($2);
 	    }
+          | '.'
+            {
+		    $$ = forlan_node_create(forlan_type_comp);
+		    $$->comp.abs = 1;
+		    $$->comp.node = NULL;
+	    }
           | LAST
             {
 		    $$ = forlan_node_create(forlan_type_last);
@@ -175,14 +181,54 @@ string    : IDENT
 
 funcall   : IDENT '(' ')'
             {
+		    struct forlan_function *fp =
+			    forlan_find_function($1);
+		    if (!fp) {
+			    grecs_error(&@1, 0,
+					"call to unknown function \"%s\"",
+					$1);
+			    YYERROR;
+		    }
+
+		    if (fp->minargs != 0) {
+			    grecs_error(&@1, 0,
+					"not enough arguments in call to \"%s\"",
+					$1);
+			    YYERROR;
+		    }
+		    
 		    $$ = forlan_node_create(forlan_type_func);
-		    $$->func.fp = $1; //FIXME
+		    $$->func.fp = fp;
 		    $$->func.args = NULL;
 	    }
           | IDENT '(' arglist ')'
             {
+		    struct forlan_function *fp =
+			    forlan_find_function($1);
+		    if (!fp) {
+			    grecs_error(&@1, 0,
+					"call to unknown function \"%s\"",
+					$1);
+			    YYERROR;
+		    }
+
+		    if ($3->count < fp->minargs) {
+			    grecs_error(&@1, 0,
+					"not enough arguments in call to \"%s\"",
+					$1);
+			    YYERROR;
+		    }
+		    if (fp->maxargs >= 0 && $3->count > fp->minargs) {
+			    grecs_error(&@1, 0,
+					"too many arguments in call to \"%s\"",
+					$1);
+			    YYERROR;
+		    }
+
+		    /* FIXME: Check data types */
+		    
 		    $$ = forlan_node_create(forlan_type_func);
-		    $$->func.fp = $1; //FIXME
+		    $$->func.fp = fp;
 		    $$->func.args = $3;
 	    }
           ;