Index: uspace/app/sbi/src/builtin_t.h
===================================================================
--- uspace/app/sbi/src/builtin_t.h	(revision 4204ad9995854e56dae719be52c05abf90dee4e7)
+++ uspace/app/sbi/src/builtin_t.h	(revision 4204ad9995854e56dae719be52c05abf90dee4e7)
@@ -0,0 +1,49 @@
+/*
+ * Copyright (c) 2010 Jiri Svoboda
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * - Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ * - Redistributions in binary form must reproduce the above copyright
+ *   notice, this list of conditions and the following disclaimer in the
+ *   documentation and/or other materials provided with the distribution.
+ * - The name of the author may not be used to endorse or promote products
+ *   derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef BUILTIN_T_H_
+#define BUILTIN_T_H_
+
+#include "run_t.h"
+
+/** Builtin symbols object
+ *
+ * Aggregates references to builtin symbols.
+ */
+typedef struct builtin {
+	/** Containing program object */
+	struct stree_program *program;
+
+	/** Grandfather object */
+	struct stree_symbol *gf_class;
+} builtin_t;
+
+/** Callback to run for a builtin procedure */
+typedef void (*builtin_proc_t)(run_t *);
+
+#endif
Index: uspace/app/sbi/src/imode.c
===================================================================
--- uspace/app/sbi/src/imode.c	(revision 4204ad9995854e56dae719be52c05abf90dee4e7)
+++ uspace/app/sbi/src/imode.c	(revision 4204ad9995854e56dae719be52c05abf90dee4e7)
@@ -0,0 +1,119 @@
+/*
+ * Copyright (c) 2010 Jiri Svoboda
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * - Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ * - Redistributions in binary form must reproduce the above copyright
+ *   notice, this list of conditions and the following disclaimer in the
+ *   documentation and/or other materials provided with the distribution.
+ * - The name of the author may not be used to endorse or promote products
+ *   derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+/** @file Interactive mode. */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include "ancr.h"
+#include "builtin.h"
+#include "list.h"
+#include "mytypes.h"
+#include "stree.h"
+#include "strtab.h"
+#include "stype.h"
+#include "input.h"
+#include "lex.h"
+#include "parse.h"
+#include "run.h"
+
+#include "imode.h"
+
+void imode_run(void)
+{
+	input_t *input;
+	lex_t lex;
+	parse_t parse;
+	stree_program_t *program;
+	stree_stat_t *stat;
+	stree_proc_t *proc;
+	stree_fun_t *fun;
+	stree_symbol_t *fun_sym;
+	stype_t stype;
+
+	run_t run;
+	run_proc_ar_t *proc_ar;
+
+	bool_t quit_im;
+
+	/* Create an empty program. */
+	program = stree_program_new();
+	program->module = stree_module_new();
+
+	/* Declare builtin symbols. */
+	builtin_declare(program);
+
+	/* Resolve ancestry. */
+	ancr_module_process(program, program->module);
+
+	quit_im = b_false;
+	while (quit_im != b_true) {
+		input_new_interactive(&input);
+
+		/* Parse input. */
+		lex_init(&lex, input);
+		parse_init(&parse, program, &lex);
+
+		if (lcur_lc(&parse) == lc_eof)
+			break;
+
+		stat = parse_stat(&parse);
+
+		/* Construct typing context. */
+		stype.program = program;
+		stype.proc_vr = stype_proc_vr_new();
+		stype.current_csi = NULL;
+		proc = stree_proc_new();
+
+		fun = stree_fun_new();
+		fun_sym = stree_symbol_new(sc_fun);
+		fun_sym->u.fun = fun;
+		fun->name = stree_ident_new();
+		fun->name->sid = strtab_get_sid("$imode");
+
+		stype.proc_vr->proc = proc;
+		fun->symbol = fun_sym;
+		proc->outer_symbol = fun_sym;
+
+		/* Construct run context. */
+		run.thread_ar = run_thread_ar_new();
+		list_init(&run.thread_ar->proc_ar);
+		run_proc_ar_create(&run, NULL, proc, &proc_ar);
+		list_append(&run.thread_ar->proc_ar, proc_ar);
+
+		/* Type statement. */
+		stype_stat(&stype, stat);
+
+		/* Run statement. */
+		run_init(&run);
+		run.program = program;
+		run_stat(&run, stat);
+	}
+
+	printf("\nBye!\n");
+}
Index: uspace/app/sbi/src/imode.h
===================================================================
--- uspace/app/sbi/src/imode.h	(revision 4204ad9995854e56dae719be52c05abf90dee4e7)
+++ uspace/app/sbi/src/imode.h	(revision 4204ad9995854e56dae719be52c05abf90dee4e7)
@@ -0,0 +1,34 @@
+/*
+ * Copyright (c) 2010 Jiri Svoboda
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * - Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ * - Redistributions in binary form must reproduce the above copyright
+ *   notice, this list of conditions and the following disclaimer in the
+ *   documentation and/or other materials provided with the distribution.
+ * - The name of the author may not be used to endorse or promote products
+ *   derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifndef IMODE_H_
+#define IMODE_H_
+
+void imode_run(void);
+
+#endif