diff --git a/src/Make_cyg_ming.mak b/src/Make_cyg_ming.mak
index 1c519d9..d8b4db1 100644
--- a/src/Make_cyg_ming.mak
+++ b/src/Make_cyg_ming.mak
@@ -806,6 +806,7 @@
 	$(OUTDIR)/vim9compile.o \
 	$(OUTDIR)/vim9execute.o \
 	$(OUTDIR)/vim9script.o \
+	$(OUTDIR)/vim9type.o \
 	$(OUTDIR)/viminfo.o \
 	$(OUTDIR)/winclip.o \
 	$(OUTDIR)/window.o
@@ -1177,6 +1178,8 @@
 
 $(OUTDIR)/vim9script.o: vim9script.c $(INCL) version.h
 
+$(OUTDIR)/vim9type.o: vim9type.c $(INCL) version.h
+
 $(OUTDIR)/viminfo.o: viminfo.c $(INCL) version.h
 
 $(OUTDIR)/gui_dwrite.o:	gui_dwrite.cpp gui_dwrite.h
diff --git a/src/Make_mvc.mak b/src/Make_mvc.mak
index d66ff71..9c3deb6 100644
--- a/src/Make_mvc.mak
+++ b/src/Make_mvc.mak
@@ -825,6 +825,7 @@
 	$(OUTDIR)\vim9compile.obj \
 	$(OUTDIR)\vim9execute.obj \
 	$(OUTDIR)\vim9script.obj \
+	$(OUTDIR)\vim9type.obj \
 	$(OUTDIR)\viminfo.obj \
 	$(OUTDIR)\winclip.obj \
 	$(OUTDIR)\window.obj \
@@ -1799,6 +1800,8 @@
 
 $(OUTDIR)/vim9script.obj:	$(OUTDIR) vim9script.c  $(INCL)
 
+$(OUTDIR)/vim9type.obj:	$(OUTDIR) vim9type.c  $(INCL)
+
 $(OUTDIR)/viminfo.obj:	$(OUTDIR) viminfo.c  $(INCL) version.h
 
 $(OUTDIR)/window.obj:	$(OUTDIR) window.c  $(INCL)
@@ -1998,6 +2001,7 @@
 	proto/vim9compile.pro \
 	proto/vim9execute.pro \
 	proto/vim9script.pro \
+	proto/vim9type.pro \
 	proto/viminfo.pro \
 	proto/window.pro \
 	$(SOUND_PRO) \
diff --git a/src/Makefile b/src/Makefile
index 148126d..55c3664 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -1702,6 +1702,7 @@
 	vim9compile.c \
 	vim9execute.c \
 	vim9script.c \
+	vim9type.c \
 	viminfo.c \
 	window.c \
 	bufwrite.c \
@@ -1851,6 +1852,7 @@
 	objects/vim9compile.o \
 	objects/vim9execute.o \
 	objects/vim9script.o \
+	objects/vim9type.o \
 	objects/viminfo.o \
 	objects/window.o \
 	objects/bufwrite.o \
@@ -2032,6 +2034,7 @@
 	vim9compile.pro \
 	vim9execute.pro \
 	vim9script.pro \
+	vim9type.pro \
 	viminfo.pro \
 	window.pro \
 	$(ALL_GUI_PRO) \
@@ -3563,6 +3566,9 @@
 objects/vim9script.o: vim9script.c
 	$(CCC) -o $@ vim9script.c
 
+objects/vim9type.o: vim9type.c
+	$(CCC) -o $@ vim9type.c
+
 objects/viminfo.o: viminfo.c
 	$(CCC) -o $@ viminfo.c
 
@@ -4192,6 +4198,10 @@
  os_unix.h auto/osdef.h ascii.h keymap.h term.h macros.h option.h beval.h \
  proto/gui_beval.pro structs.h regexp.h gui.h alloc.h ex_cmds.h spell.h \
  proto.h globals.h vim9.h
+objects/vim9type.o: vim9type.c vim.h protodef.h auto/config.h feature.h \
+ os_unix.h auto/osdef.h ascii.h keymap.h term.h macros.h option.h beval.h \
+ proto/gui_beval.pro structs.h regexp.h gui.h alloc.h ex_cmds.h spell.h \
+ proto.h globals.h vim9.h
 objects/viminfo.o: viminfo.c vim.h protodef.h auto/config.h feature.h os_unix.h \
  auto/osdef.h ascii.h keymap.h term.h macros.h option.h beval.h \
  proto/gui_beval.pro structs.h regexp.h gui.h alloc.h ex_cmds.h spell.h \
diff --git a/src/proto.h b/src/proto.h
index 95fd81a..e894987 100644
--- a/src/proto.h
+++ b/src/proto.h
@@ -237,6 +237,7 @@
 #  include "vim9compile.pro"
 #  include "vim9execute.pro"
 #  include "vim9script.pro"
+#  include "vim9type.pro"
 # endif
 # include "window.pro"
 
diff --git a/src/proto/vim9compile.pro b/src/proto/vim9compile.pro
index 2de542b..80d0b25 100644
--- a/src/proto/vim9compile.pro
+++ b/src/proto/vim9compile.pro
@@ -1,15 +1,6 @@
 /* vim9compile.c */
 int check_defined(char_u *p, size_t len, cctx_T *cctx);
-void clear_type_list(garray_T *gap);
-type_T *typval2type(typval_T *tv, garray_T *type_gap);
-type_T *typval2type_vimvar(typval_T *tv, garray_T *type_gap);
-int check_typval_type(type_T *expected, typval_T *actual_tv);
-int check_type(type_T *expected, type_T *actual, int give_msg);
 int check_compare_types(exptype_T type, typval_T *tv1, typval_T *tv2);
-char_u *skip_type(char_u *start, int optional);
-type_T *parse_type(char_u **arg, garray_T *type_gap);
-char *vartype_name(vartype_T type);
-char *type_name(type_T *type, char **tofree);
 int get_script_item_idx(int sid, char_u *name, int check_writable);
 imported_T *find_imported(char_u *name, size_t len, cctx_T *cctx);
 imported_T *find_imported_in_script(char_u *name, size_t len, int sid);
diff --git a/src/proto/vim9type.pro b/src/proto/vim9type.pro
new file mode 100644
index 0000000..5c7ba03
--- /dev/null
+++ b/src/proto/vim9type.pro
@@ -0,0 +1,19 @@
+/* vim9type.c */
+void clear_type_list(garray_T *gap);
+type_T *get_list_type(type_T *member_type, garray_T *type_gap);
+type_T *get_dict_type(type_T *member_type, garray_T *type_gap);
+type_T *alloc_func_type(type_T *ret_type, int argcount, garray_T *type_gap);
+type_T *get_func_type(type_T *ret_type, int argcount, garray_T *type_gap);
+int func_type_add_arg_types(type_T *functype, int argcount, garray_T *type_gap);
+type_T *typval2type(typval_T *tv, garray_T *type_gap);
+type_T *typval2type_vimvar(typval_T *tv, garray_T *type_gap);
+int check_typval_type(type_T *expected, typval_T *actual_tv);
+void type_mismatch(type_T *expected, type_T *actual);
+void arg_type_mismatch(type_T *expected, type_T *actual, int argidx);
+int check_type(type_T *expected, type_T *actual, int give_msg);
+char_u *skip_type(char_u *start, int optional);
+type_T *parse_type(char_u **arg, garray_T *type_gap);
+void common_type(type_T *type1, type_T *type2, type_T **dest, garray_T *type_gap);
+char *vartype_name(vartype_T type);
+char *type_name(type_T *type, char **tofree);
+/* vim: set ft=c : */
diff --git a/src/version.c b/src/version.c
index 4adf44f..168ee02 100644
--- a/src/version.c
+++ b/src/version.c
@@ -755,6 +755,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1405,
+/**/
     1404,
 /**/
     1403,
diff --git a/src/vim9compile.c b/src/vim9compile.c
index a47d3d9..e23dd7a 100644
--- a/src/vim9compile.c
+++ b/src/vim9compile.c
@@ -151,7 +151,6 @@
 static char e_unknown_var[] = N_("E1089: unknown variable: %s");
 
 static void delete_def_function_contents(dfunc_T *dfunc);
-static void arg_type_mismatch(type_T *expected, type_T *actual, int argidx);
 
 /*
  * Lookup variable "name" in the local scope and return it.
@@ -310,374 +309,6 @@
     return OK;
 }
 
-/*
- * Allocate memory for a type_T and add the pointer to type_gap, so that it can
- * be freed later.
- */
-    static type_T *
-alloc_type(garray_T *type_gap)
-{
-    type_T *type;
-
-    if (ga_grow(type_gap, 1) == FAIL)
-	return NULL;
-    type = ALLOC_CLEAR_ONE(type_T);
-    if (type != NULL)
-    {
-	((type_T **)type_gap->ga_data)[type_gap->ga_len] = type;
-	++type_gap->ga_len;
-    }
-    return type;
-}
-
-    void
-clear_type_list(garray_T *gap)
-{
-    while (gap->ga_len > 0)
-	vim_free(((type_T **)gap->ga_data)[--gap->ga_len]);
-    ga_clear(gap);
-}
-
-    static type_T *
-get_list_type(type_T *member_type, garray_T *type_gap)
-{
-    type_T *type;
-
-    // recognize commonly used types
-    if (member_type->tt_type == VAR_ANY)
-	return &t_list_any;
-    if (member_type->tt_type == VAR_VOID
-	    || member_type->tt_type == VAR_UNKNOWN)
-	return &t_list_empty;
-    if (member_type->tt_type == VAR_BOOL)
-	return &t_list_bool;
-    if (member_type->tt_type == VAR_NUMBER)
-	return &t_list_number;
-    if (member_type->tt_type == VAR_STRING)
-	return &t_list_string;
-
-    // Not a common type, create a new entry.
-    type = alloc_type(type_gap);
-    if (type == NULL)
-	return &t_any;
-    type->tt_type = VAR_LIST;
-    type->tt_member = member_type;
-    type->tt_argcount = 0;
-    type->tt_args = NULL;
-    return type;
-}
-
-    static type_T *
-get_dict_type(type_T *member_type, garray_T *type_gap)
-{
-    type_T *type;
-
-    // recognize commonly used types
-    if (member_type->tt_type == VAR_ANY)
-	return &t_dict_any;
-    if (member_type->tt_type == VAR_VOID
-	    || member_type->tt_type == VAR_UNKNOWN)
-	return &t_dict_empty;
-    if (member_type->tt_type == VAR_BOOL)
-	return &t_dict_bool;
-    if (member_type->tt_type == VAR_NUMBER)
-	return &t_dict_number;
-    if (member_type->tt_type == VAR_STRING)
-	return &t_dict_string;
-
-    // Not a common type, create a new entry.
-    type = alloc_type(type_gap);
-    if (type == NULL)
-	return &t_any;
-    type->tt_type = VAR_DICT;
-    type->tt_member = member_type;
-    type->tt_argcount = 0;
-    type->tt_args = NULL;
-    return type;
-}
-
-/*
- * Allocate a new type for a function.
- */
-    static type_T *
-alloc_func_type(type_T *ret_type, int argcount, garray_T *type_gap)
-{
-    type_T *type = alloc_type(type_gap);
-
-    if (type == NULL)
-	return &t_any;
-    type->tt_type = VAR_FUNC;
-    type->tt_member = ret_type;
-    type->tt_argcount = argcount;
-    type->tt_args = NULL;
-    return type;
-}
-
-/*
- * Get a function type, based on the return type "ret_type".
- * If "argcount" is -1 or 0 a predefined type can be used.
- * If "argcount" > 0 always create a new type, so that arguments can be added.
- */
-    static type_T *
-get_func_type(type_T *ret_type, int argcount, garray_T *type_gap)
-{
-    // recognize commonly used types
-    if (argcount <= 0)
-    {
-	if (ret_type == &t_unknown)
-	{
-	    // (argcount == 0) is not possible
-	    return &t_func_unknown;
-	}
-	if (ret_type == &t_void)
-	{
-	    if (argcount == 0)
-		return &t_func_0_void;
-	    else
-		return &t_func_void;
-	}
-	if (ret_type == &t_any)
-	{
-	    if (argcount == 0)
-		return &t_func_0_any;
-	    else
-		return &t_func_any;
-	}
-	if (ret_type == &t_number)
-	{
-	    if (argcount == 0)
-		return &t_func_0_number;
-	    else
-		return &t_func_number;
-	}
-	if (ret_type == &t_string)
-	{
-	    if (argcount == 0)
-		return &t_func_0_string;
-	    else
-		return &t_func_string;
-	}
-    }
-
-    return alloc_func_type(ret_type, argcount, type_gap);
-}
-
-/*
- * For a function type, reserve space for "argcount" argument types (including
- * vararg).
- */
-    static int
-func_type_add_arg_types(
-	type_T	    *functype,
-	int	    argcount,
-	garray_T    *type_gap)
-{
-    // To make it easy to free the space needed for the argument types, add the
-    // pointer to type_gap.
-    if (ga_grow(type_gap, 1) == FAIL)
-	return FAIL;
-    functype->tt_args = ALLOC_CLEAR_MULT(type_T *, argcount);
-    if (functype->tt_args == NULL)
-	return FAIL;
-    ((type_T **)type_gap->ga_data)[type_gap->ga_len] =
-						     (void *)functype->tt_args;
-    ++type_gap->ga_len;
-    return OK;
-}
-
-/*
- * Get a type_T for a typval_T.
- * "type_list" is used to temporarily create types in.
- */
-    type_T *
-typval2type(typval_T *tv, garray_T *type_gap)
-{
-    type_T  *actual;
-    type_T  *member_type;
-
-    if (tv->v_type == VAR_NUMBER)
-	return &t_number;
-    if (tv->v_type == VAR_BOOL)
-	return &t_bool;  // not used
-    if (tv->v_type == VAR_STRING)
-	return &t_string;
-
-    if (tv->v_type == VAR_LIST)
-    {
-	if (tv->vval.v_list == NULL || tv->vval.v_list->lv_first == NULL)
-	    return &t_list_empty;
-
-	// Use the type of the first member, it is the most specific.
-	member_type = typval2type(&tv->vval.v_list->lv_first->li_tv, type_gap);
-	return get_list_type(member_type, type_gap);
-    }
-
-    if (tv->v_type == VAR_DICT)
-    {
-	dict_iterator_T iter;
-	typval_T	*value;
-
-	if (tv->vval.v_dict == NULL
-				   || tv->vval.v_dict->dv_hashtab.ht_used == 0)
-	    return &t_dict_empty;
-
-	// Use the type of the first value, it is the most specific.
-	dict_iterate_start(tv, &iter);
-	dict_iterate_next(&iter, &value);
-	member_type = typval2type(value, type_gap);
-	return get_dict_type(member_type, type_gap);
-    }
-
-    if (tv->v_type == VAR_FUNC || tv->v_type == VAR_PARTIAL)
-    {
-	char_u	*name = NULL;
-	ufunc_T *ufunc = NULL;
-
-	if (tv->v_type == VAR_PARTIAL)
-	{
-	    if (tv->vval.v_partial->pt_func != NULL)
-		ufunc = tv->vval.v_partial->pt_func;
-	    else
-		name = tv->vval.v_partial->pt_name;
-	}
-	else
-	    name = tv->vval.v_string;
-	if (name != NULL)
-	    // TODO: how about a builtin function?
-	    ufunc = find_func(name, FALSE, NULL);
-	if (ufunc != NULL)
-	{
-	    // May need to get the argument types from default values by
-	    // compiling the function.
-	    if (ufunc->uf_def_status == UF_TO_BE_COMPILED
-			    && compile_def_function(ufunc, TRUE, NULL) == FAIL)
-		return NULL;
-	    if (ufunc->uf_func_type != NULL)
-		return ufunc->uf_func_type;
-	}
-    }
-
-    actual = alloc_type(type_gap);
-    if (actual == NULL)
-	return NULL;
-    actual->tt_type = tv->v_type;
-    actual->tt_member = &t_any;
-
-    return actual;
-}
-
-/*
- * Get a type_T for a typval_T, used for v: variables.
- * "type_list" is used to temporarily create types in.
- */
-    type_T *
-typval2type_vimvar(typval_T *tv, garray_T *type_gap)
-{
-    if (tv->v_type == VAR_LIST)  // e.g. for v:oldfiles
-	return &t_list_string;
-    if (tv->v_type == VAR_DICT)  // e.g. for v:completed_item
-	return &t_dict_any;
-    return typval2type(tv, type_gap);
-}
-
-
-/*
- * Return FAIL if "expected" and "actual" don't match.
- */
-    int
-check_typval_type(type_T *expected, typval_T *actual_tv)
-{
-    garray_T	type_list;
-    type_T	*actual_type;
-    int		res = FAIL;
-
-    ga_init2(&type_list, sizeof(type_T *), 10);
-    actual_type = typval2type(actual_tv, &type_list);
-    if (actual_type != NULL)
-	res = check_type(expected, actual_type, TRUE);
-    clear_type_list(&type_list);
-    return res;
-}
-
-    static void
-type_mismatch(type_T *expected, type_T *actual)
-{
-    char *tofree1, *tofree2;
-
-    semsg(_("E1013: type mismatch, expected %s but got %s"),
-		   type_name(expected, &tofree1), type_name(actual, &tofree2));
-    vim_free(tofree1);
-    vim_free(tofree2);
-}
-
-    static void
-arg_type_mismatch(type_T *expected, type_T *actual, int argidx)
-{
-    char *tofree1, *tofree2;
-
-    semsg(_("E1013: argument %d: type mismatch, expected %s but got %s"),
-	    argidx,
-	    type_name(expected, &tofree1), type_name(actual, &tofree2));
-    vim_free(tofree1);
-    vim_free(tofree2);
-}
-
-/*
- * Check if the expected and actual types match.
- * Does not allow for assigning "any" to a specific type.
- */
-    int
-check_type(type_T *expected, type_T *actual, int give_msg)
-{
-    int ret = OK;
-
-    // When expected is "unknown" we accept any actual type.
-    // When expected is "any" we accept any actual type except "void".
-    if (expected->tt_type != VAR_UNKNOWN
-	    && !(expected->tt_type == VAR_ANY && actual->tt_type != VAR_VOID))
-
-    {
-	if (expected->tt_type != actual->tt_type)
-	{
-	    if (give_msg)
-		type_mismatch(expected, actual);
-	    return FAIL;
-	}
-	if (expected->tt_type == VAR_DICT || expected->tt_type == VAR_LIST)
-	{
-	    // "unknown" is used for an empty list or dict
-	    if (actual->tt_member != &t_unknown)
-		ret = check_type(expected->tt_member, actual->tt_member, FALSE);
-	}
-	else if (expected->tt_type == VAR_FUNC)
-	{
-	    if (expected->tt_member != &t_unknown)
-		ret = check_type(expected->tt_member, actual->tt_member, FALSE);
-	    if (ret == OK && expected->tt_argcount != -1
-		    && (actual->tt_argcount < expected->tt_min_argcount
-			|| actual->tt_argcount > expected->tt_argcount))
-		    ret = FAIL;
-	    if (expected->tt_args != NULL && actual->tt_args != NULL)
-	    {
-		int i;
-
-		for (i = 0; i < expected->tt_argcount; ++i)
-		    // Allow for using "any" argument type, lambda's have them.
-		    if (actual->tt_args[i] != &t_any && check_type(
-			       expected->tt_args[i], actual->tt_args[i], FALSE)
-								       == FAIL)
-		    {
-			ret = FAIL;
-			break;
-		    }
-	    }
-	}
-	if (ret == FAIL && give_msg)
-	    type_mismatch(expected, actual);
-    }
-    return ret;
-}
-
 
 /////////////////////////////////////////////////////////////////////
 // Following generate_ functions expect the caller to call ga_grow().
@@ -1982,529 +1613,6 @@
 }
 
 /*
- * Skip over a type definition and return a pointer to just after it.
- * When "optional" is TRUE then a leading "?" is accepted.
- */
-    char_u *
-skip_type(char_u *start, int optional)
-{
-    char_u *p = start;
-
-    if (optional && *p == '?')
-	++p;
-    while (ASCII_ISALNUM(*p) || *p == '_')
-	++p;
-
-    // Skip over "<type>"; this is permissive about white space.
-    if (*skipwhite(p) == '<')
-    {
-	p = skipwhite(p);
-	p = skip_type(skipwhite(p + 1), FALSE);
-	p = skipwhite(p);
-	if (*p == '>')
-	    ++p;
-    }
-    else if ((*p == '(' || (*p == ':' && VIM_ISWHITE(p[1])))
-					     && STRNCMP("func", start, 4) == 0)
-    {
-	if (*p == '(')
-	{
-	    // handle func(args): type
-	    ++p;
-	    while (*p != ')' && *p != NUL)
-	    {
-		char_u *sp = p;
-
-		if (STRNCMP(p, "...", 3) == 0)
-		    p += 3;
-		p = skip_type(p, TRUE);
-		if (p == sp)
-		    return p;  // syntax error
-		if (*p == ',')
-		    p = skipwhite(p + 1);
-	    }
-	    if (*p == ')')
-	    {
-		if (p[1] == ':')
-		    p = skip_type(skipwhite(p + 2), FALSE);
-		else
-		    ++p;
-	    }
-	}
-	else
-	{
-	    // handle func: return_type
-	    p = skip_type(skipwhite(p + 1), FALSE);
-	}
-    }
-
-    return p;
-}
-
-/*
- * Parse the member type: "<type>" and return "type" with the member set.
- * Use "type_gap" if a new type needs to be added.
- * Returns NULL in case of failure.
- */
-    static type_T *
-parse_type_member(char_u **arg, type_T *type, garray_T *type_gap)
-{
-    type_T  *member_type;
-    int	    prev_called_emsg = called_emsg;
-
-    if (**arg != '<')
-    {
-	if (*skipwhite(*arg) == '<')
-	    semsg(_(e_no_white_before), "<");
-	else
-	    emsg(_("E1008: Missing <type>"));
-	return type;
-    }
-    *arg = skipwhite(*arg + 1);
-
-    member_type = parse_type(arg, type_gap);
-
-    *arg = skipwhite(*arg);
-    if (**arg != '>' && called_emsg == prev_called_emsg)
-    {
-	emsg(_("E1009: Missing > after type"));
-	return type;
-    }
-    ++*arg;
-
-    if (type->tt_type == VAR_LIST)
-	return get_list_type(member_type, type_gap);
-    return get_dict_type(member_type, type_gap);
-}
-
-/*
- * Parse a type at "arg" and advance over it.
- * Return &t_any for failure.
- */
-    type_T *
-parse_type(char_u **arg, garray_T *type_gap)
-{
-    char_u  *p = *arg;
-    size_t  len;
-
-    // skip over the first word
-    while (ASCII_ISALNUM(*p) || *p == '_')
-	++p;
-    len = p - *arg;
-
-    switch (**arg)
-    {
-	case 'a':
-	    if (len == 3 && STRNCMP(*arg, "any", len) == 0)
-	    {
-		*arg += len;
-		return &t_any;
-	    }
-	    break;
-	case 'b':
-	    if (len == 4 && STRNCMP(*arg, "bool", len) == 0)
-	    {
-		*arg += len;
-		return &t_bool;
-	    }
-	    if (len == 4 && STRNCMP(*arg, "blob", len) == 0)
-	    {
-		*arg += len;
-		return &t_blob;
-	    }
-	    break;
-	case 'c':
-	    if (len == 7 && STRNCMP(*arg, "channel", len) == 0)
-	    {
-		*arg += len;
-		return &t_channel;
-	    }
-	    break;
-	case 'd':
-	    if (len == 4 && STRNCMP(*arg, "dict", len) == 0)
-	    {
-		*arg += len;
-		return parse_type_member(arg, &t_dict_any, type_gap);
-	    }
-	    break;
-	case 'f':
-	    if (len == 5 && STRNCMP(*arg, "float", len) == 0)
-	    {
-#ifdef FEAT_FLOAT
-		*arg += len;
-		return &t_float;
-#else
-		emsg(_("E1076: This Vim is not compiled with float support"));
-		return &t_any;
-#endif
-	    }
-	    if (len == 4 && STRNCMP(*arg, "func", len) == 0)
-	    {
-		type_T  *type;
-		type_T  *ret_type = &t_unknown;
-		int	argcount = -1;
-		int	flags = 0;
-		int	first_optional = -1;
-		type_T	*arg_type[MAX_FUNC_ARGS + 1];
-
-		// func({type}, ...{type}): {type}
-		*arg += len;
-		if (**arg == '(')
-		{
-		    // "func" may or may not return a value, "func()" does
-		    // not return a value.
-		    ret_type = &t_void;
-
-		    p = ++*arg;
-		    argcount = 0;
-		    while (*p != NUL && *p != ')')
-		    {
-			if (*p == '?')
-			{
-			    if (first_optional == -1)
-				first_optional = argcount;
-			    ++p;
-			}
-			else if (STRNCMP(p, "...", 3) == 0)
-			{
-			    flags |= TTFLAG_VARARGS;
-			    p += 3;
-			}
-			else if (first_optional != -1)
-			{
-			    emsg(_("E1007: mandatory argument after optional argument"));
-			    return &t_any;
-			}
-
-			arg_type[argcount++] = parse_type(&p, type_gap);
-
-			// Nothing comes after "...{type}".
-			if (flags & TTFLAG_VARARGS)
-			    break;
-
-			if (*p != ',' && *skipwhite(p) == ',')
-			{
-			    semsg(_(e_no_white_before), ",");
-			    return &t_any;
-			}
-			if (*p == ',')
-			{
-			    ++p;
-			    if (!VIM_ISWHITE(*p))
-			    {
-				semsg(_(e_white_after), ",");
-				return &t_any;
-			    }
-			}
-			p = skipwhite(p);
-			if (argcount == MAX_FUNC_ARGS)
-			{
-			    emsg(_("E740: Too many argument types"));
-			    return &t_any;
-			}
-		    }
-
-		    p = skipwhite(p);
-		    if (*p != ')')
-		    {
-			emsg(_(e_missing_close));
-			return &t_any;
-		    }
-		    *arg = p + 1;
-		}
-		if (**arg == ':')
-		{
-		    // parse return type
-		    ++*arg;
-		    if (!VIM_ISWHITE(**arg))
-			semsg(_(e_white_after), ":");
-		    *arg = skipwhite(*arg);
-		    ret_type = parse_type(arg, type_gap);
-		}
-		if (flags == 0 && first_optional == -1 && argcount <= 0)
-		    type = get_func_type(ret_type, argcount, type_gap);
-		else
-		{
-		    type = alloc_func_type(ret_type, argcount, type_gap);
-		    type->tt_flags = flags;
-		    if (argcount > 0)
-		    {
-			type->tt_argcount = argcount;
-			type->tt_min_argcount = first_optional == -1
-						   ? argcount : first_optional;
-			if (func_type_add_arg_types(type, argcount,
-							     type_gap) == FAIL)
-			    return &t_any;
-			mch_memmove(type->tt_args, arg_type,
-						  sizeof(type_T *) * argcount);
-		    }
-		}
-		return type;
-	    }
-	    break;
-	case 'j':
-	    if (len == 3 && STRNCMP(*arg, "job", len) == 0)
-	    {
-		*arg += len;
-		return &t_job;
-	    }
-	    break;
-	case 'l':
-	    if (len == 4 && STRNCMP(*arg, "list", len) == 0)
-	    {
-		*arg += len;
-		return parse_type_member(arg, &t_list_any, type_gap);
-	    }
-	    break;
-	case 'n':
-	    if (len == 6 && STRNCMP(*arg, "number", len) == 0)
-	    {
-		*arg += len;
-		return &t_number;
-	    }
-	    break;
-	case 's':
-	    if (len == 6 && STRNCMP(*arg, "string", len) == 0)
-	    {
-		*arg += len;
-		return &t_string;
-	    }
-	    break;
-	case 'v':
-	    if (len == 4 && STRNCMP(*arg, "void", len) == 0)
-	    {
-		*arg += len;
-		return &t_void;
-	    }
-	    break;
-    }
-
-    semsg(_("E1010: Type not recognized: %s"), *arg);
-    return &t_any;
-}
-
-/*
- * Check if "type1" and "type2" are exactly the same.
- */
-    static int
-equal_type(type_T *type1, type_T *type2)
-{
-    int i;
-
-    if (type1->tt_type != type2->tt_type)
-	return FALSE;
-    switch (type1->tt_type)
-    {
-	case VAR_UNKNOWN:
-	case VAR_ANY:
-	case VAR_VOID:
-	case VAR_SPECIAL:
-	case VAR_BOOL:
-	case VAR_NUMBER:
-	case VAR_FLOAT:
-	case VAR_STRING:
-	case VAR_BLOB:
-	case VAR_JOB:
-	case VAR_CHANNEL:
-	    break;  // not composite is always OK
-	case VAR_LIST:
-	case VAR_DICT:
-	    return equal_type(type1->tt_member, type2->tt_member);
-	case VAR_FUNC:
-	case VAR_PARTIAL:
-	    if (!equal_type(type1->tt_member, type2->tt_member)
-		    || type1->tt_argcount != type2->tt_argcount)
-		return FALSE;
-	    if (type1->tt_argcount < 0
-			   || type1->tt_args == NULL || type2->tt_args == NULL)
-		return TRUE;
-	    for (i = 0; i < type1->tt_argcount; ++i)
-		if (!equal_type(type1->tt_args[i], type2->tt_args[i]))
-		    return FALSE;
-	    return TRUE;
-    }
-    return TRUE;
-}
-
-/*
- * Find the common type of "type1" and "type2" and put it in "dest".
- * "type2" and "dest" may be the same.
- */
-    static void
-common_type(type_T *type1, type_T *type2, type_T **dest, garray_T *type_gap)
-{
-    if (equal_type(type1, type2))
-    {
-	*dest = type1;
-	return;
-    }
-
-    if (type1->tt_type == type2->tt_type)
-    {
-	if (type1->tt_type == VAR_LIST || type2->tt_type == VAR_DICT)
-	{
-	    type_T *common;
-
-	    common_type(type1->tt_member, type2->tt_member, &common, type_gap);
-	    if (type1->tt_type == VAR_LIST)
-		*dest = get_list_type(common, type_gap);
-	    else
-		*dest = get_dict_type(common, type_gap);
-	    return;
-	}
-	if (type1->tt_type == VAR_FUNC)
-	{
-	    type_T *common;
-
-	    common_type(type1->tt_member, type2->tt_member, &common, type_gap);
-	    if (type1->tt_argcount == type2->tt_argcount
-						    && type1->tt_argcount >= 0)
-	    {
-		int argcount = type1->tt_argcount;
-		int i;
-
-		*dest = alloc_func_type(common, argcount, type_gap);
-		if (type1->tt_args != NULL && type2->tt_args != NULL)
-		{
-		    if (func_type_add_arg_types(*dest, argcount,
-							     type_gap) == OK)
-			for (i = 0; i < argcount; ++i)
-			    common_type(type1->tt_args[i], type2->tt_args[i],
-					       &(*dest)->tt_args[i], type_gap);
-		}
-	    }
-	    else
-		*dest = alloc_func_type(common, -1, type_gap);
-	    return;
-	}
-    }
-
-    *dest = &t_any;
-}
-
-    char *
-vartype_name(vartype_T type)
-{
-    switch (type)
-    {
-	case VAR_UNKNOWN: break;
-	case VAR_ANY: return "any";
-	case VAR_VOID: return "void";
-	case VAR_SPECIAL: return "special";
-	case VAR_BOOL: return "bool";
-	case VAR_NUMBER: return "number";
-	case VAR_FLOAT: return "float";
-	case VAR_STRING: return "string";
-	case VAR_BLOB: return "blob";
-	case VAR_JOB: return "job";
-	case VAR_CHANNEL: return "channel";
-	case VAR_LIST: return "list";
-	case VAR_DICT: return "dict";
-
-	case VAR_FUNC:
-	case VAR_PARTIAL: return "func";
-    }
-    return "unknown";
-}
-
-/*
- * Return the name of a type.
- * The result may be in allocated memory, in which case "tofree" is set.
- */
-    char *
-type_name(type_T *type, char **tofree)
-{
-    char *name = vartype_name(type->tt_type);
-
-    *tofree = NULL;
-    if (type->tt_type == VAR_LIST || type->tt_type == VAR_DICT)
-    {
-	char *member_free;
-	char *member_name = type_name(type->tt_member, &member_free);
-	size_t len;
-
-	len = STRLEN(name) + STRLEN(member_name) + 3;
-	*tofree = alloc(len);
-	if (*tofree != NULL)
-	{
-	    vim_snprintf(*tofree, len, "%s<%s>", name, member_name);
-	    vim_free(member_free);
-	    return *tofree;
-	}
-    }
-    if (type->tt_type == VAR_FUNC)
-    {
-	garray_T    ga;
-	int	    i;
-	int	    varargs = (type->tt_flags & TTFLAG_VARARGS) ? 1 : 0;
-
-	ga_init2(&ga, 1, 100);
-	if (ga_grow(&ga, 20) == FAIL)
-	    return "[unknown]";
-	*tofree = ga.ga_data;
-	STRCPY(ga.ga_data, "func(");
-	ga.ga_len += 5;
-
-	for (i = 0; i < type->tt_argcount; ++i)
-	{
-	    char *arg_free;
-	    char *arg_type;
-	    int  len;
-
-	    if (type->tt_args == NULL)
-		arg_type = "[unknown]";
-	    else
-		arg_type = type_name(type->tt_args[i], &arg_free);
-	    if (i > 0)
-	    {
-		STRCPY((char *)ga.ga_data + ga.ga_len, ", ");
-		ga.ga_len += 2;
-	    }
-	    len = (int)STRLEN(arg_type);
-	    if (ga_grow(&ga, len + 8) == FAIL)
-	    {
-		vim_free(arg_free);
-		return "[unknown]";
-	    }
-	    *tofree = ga.ga_data;
-	    if (varargs && i == type->tt_argcount - 1)
-	    {
-		STRCPY((char *)ga.ga_data + ga.ga_len, "...");
-		ga.ga_len += 3;
-	    }
-	    else if (i >= type->tt_min_argcount)
-		*((char *)ga.ga_data + ga.ga_len++) = '?';
-	    STRCPY((char *)ga.ga_data + ga.ga_len, arg_type);
-	    ga.ga_len += len;
-	    vim_free(arg_free);
-	}
-
-	if (type->tt_member == &t_void)
-	    STRCPY((char *)ga.ga_data + ga.ga_len, ")");
-	else
-	{
-	    char *ret_free;
-	    char *ret_name = type_name(type->tt_member, &ret_free);
-	    int  len;
-
-	    len = (int)STRLEN(ret_name) + 4;
-	    if (ga_grow(&ga, len) == FAIL)
-	    {
-		vim_free(ret_free);
-		return "[unknown]";
-	    }
-	    *tofree = ga.ga_data;
-	    STRCPY((char *)ga.ga_data + ga.ga_len, "): ");
-	    STRCPY((char *)ga.ga_data + ga.ga_len + 3, ret_name);
-	    vim_free(ret_free);
-	}
-	return ga.ga_data;
-    }
-
-    return name;
-}
-
-/*
  * Find "name" in script-local items of script "sid".
  * Returns the index in "sn_var_vals" if found.
  * If found but not in "sn_var_vals" returns -1.
diff --git a/src/vim9type.c b/src/vim9type.c
new file mode 100644
index 0000000..5cfdc66
--- /dev/null
+++ b/src/vim9type.c
@@ -0,0 +1,915 @@
+/* vi:set ts=8 sts=4 sw=4 noet:
+ *
+ * VIM - Vi IMproved	by Bram Moolenaar
+ *
+ * Do ":help uganda"  in Vim to read copying and usage conditions.
+ * Do ":help credits" in Vim to see a list of people who contributed.
+ * See README.txt for an overview of the Vim source code.
+ */
+
+/*
+ * vim9type.c: handling of types
+ */
+
+#define USING_FLOAT_STUFF
+#include "vim.h"
+
+#if defined(FEAT_EVAL) || defined(PROTO)
+
+#ifdef VMS
+# include <float.h>
+#endif
+
+/*
+ * Allocate memory for a type_T and add the pointer to type_gap, so that it can
+ * be freed later.
+ */
+    static type_T *
+alloc_type(garray_T *type_gap)
+{
+    type_T *type;
+
+    if (ga_grow(type_gap, 1) == FAIL)
+	return NULL;
+    type = ALLOC_CLEAR_ONE(type_T);
+    if (type != NULL)
+    {
+	((type_T **)type_gap->ga_data)[type_gap->ga_len] = type;
+	++type_gap->ga_len;
+    }
+    return type;
+}
+
+    void
+clear_type_list(garray_T *gap)
+{
+    while (gap->ga_len > 0)
+	vim_free(((type_T **)gap->ga_data)[--gap->ga_len]);
+    ga_clear(gap);
+}
+
+    type_T *
+get_list_type(type_T *member_type, garray_T *type_gap)
+{
+    type_T *type;
+
+    // recognize commonly used types
+    if (member_type->tt_type == VAR_ANY)
+	return &t_list_any;
+    if (member_type->tt_type == VAR_VOID
+	    || member_type->tt_type == VAR_UNKNOWN)
+	return &t_list_empty;
+    if (member_type->tt_type == VAR_BOOL)
+	return &t_list_bool;
+    if (member_type->tt_type == VAR_NUMBER)
+	return &t_list_number;
+    if (member_type->tt_type == VAR_STRING)
+	return &t_list_string;
+
+    // Not a common type, create a new entry.
+    type = alloc_type(type_gap);
+    if (type == NULL)
+	return &t_any;
+    type->tt_type = VAR_LIST;
+    type->tt_member = member_type;
+    type->tt_argcount = 0;
+    type->tt_args = NULL;
+    return type;
+}
+
+    type_T *
+get_dict_type(type_T *member_type, garray_T *type_gap)
+{
+    type_T *type;
+
+    // recognize commonly used types
+    if (member_type->tt_type == VAR_ANY)
+	return &t_dict_any;
+    if (member_type->tt_type == VAR_VOID
+	    || member_type->tt_type == VAR_UNKNOWN)
+	return &t_dict_empty;
+    if (member_type->tt_type == VAR_BOOL)
+	return &t_dict_bool;
+    if (member_type->tt_type == VAR_NUMBER)
+	return &t_dict_number;
+    if (member_type->tt_type == VAR_STRING)
+	return &t_dict_string;
+
+    // Not a common type, create a new entry.
+    type = alloc_type(type_gap);
+    if (type == NULL)
+	return &t_any;
+    type->tt_type = VAR_DICT;
+    type->tt_member = member_type;
+    type->tt_argcount = 0;
+    type->tt_args = NULL;
+    return type;
+}
+
+/*
+ * Allocate a new type for a function.
+ */
+    type_T *
+alloc_func_type(type_T *ret_type, int argcount, garray_T *type_gap)
+{
+    type_T *type = alloc_type(type_gap);
+
+    if (type == NULL)
+	return &t_any;
+    type->tt_type = VAR_FUNC;
+    type->tt_member = ret_type;
+    type->tt_argcount = argcount;
+    type->tt_args = NULL;
+    return type;
+}
+
+/*
+ * Get a function type, based on the return type "ret_type".
+ * If "argcount" is -1 or 0 a predefined type can be used.
+ * If "argcount" > 0 always create a new type, so that arguments can be added.
+ */
+    type_T *
+get_func_type(type_T *ret_type, int argcount, garray_T *type_gap)
+{
+    // recognize commonly used types
+    if (argcount <= 0)
+    {
+	if (ret_type == &t_unknown)
+	{
+	    // (argcount == 0) is not possible
+	    return &t_func_unknown;
+	}
+	if (ret_type == &t_void)
+	{
+	    if (argcount == 0)
+		return &t_func_0_void;
+	    else
+		return &t_func_void;
+	}
+	if (ret_type == &t_any)
+	{
+	    if (argcount == 0)
+		return &t_func_0_any;
+	    else
+		return &t_func_any;
+	}
+	if (ret_type == &t_number)
+	{
+	    if (argcount == 0)
+		return &t_func_0_number;
+	    else
+		return &t_func_number;
+	}
+	if (ret_type == &t_string)
+	{
+	    if (argcount == 0)
+		return &t_func_0_string;
+	    else
+		return &t_func_string;
+	}
+    }
+
+    return alloc_func_type(ret_type, argcount, type_gap);
+}
+
+/*
+ * For a function type, reserve space for "argcount" argument types (including
+ * vararg).
+ */
+    int
+func_type_add_arg_types(
+	type_T	    *functype,
+	int	    argcount,
+	garray_T    *type_gap)
+{
+    // To make it easy to free the space needed for the argument types, add the
+    // pointer to type_gap.
+    if (ga_grow(type_gap, 1) == FAIL)
+	return FAIL;
+    functype->tt_args = ALLOC_CLEAR_MULT(type_T *, argcount);
+    if (functype->tt_args == NULL)
+	return FAIL;
+    ((type_T **)type_gap->ga_data)[type_gap->ga_len] =
+						     (void *)functype->tt_args;
+    ++type_gap->ga_len;
+    return OK;
+}
+
+/*
+ * Get a type_T for a typval_T.
+ * "type_list" is used to temporarily create types in.
+ */
+    type_T *
+typval2type(typval_T *tv, garray_T *type_gap)
+{
+    type_T  *actual;
+    type_T  *member_type;
+
+    if (tv->v_type == VAR_NUMBER)
+	return &t_number;
+    if (tv->v_type == VAR_BOOL)
+	return &t_bool;  // not used
+    if (tv->v_type == VAR_STRING)
+	return &t_string;
+
+    if (tv->v_type == VAR_LIST)
+    {
+	if (tv->vval.v_list == NULL || tv->vval.v_list->lv_first == NULL)
+	    return &t_list_empty;
+
+	// Use the type of the first member, it is the most specific.
+	member_type = typval2type(&tv->vval.v_list->lv_first->li_tv, type_gap);
+	return get_list_type(member_type, type_gap);
+    }
+
+    if (tv->v_type == VAR_DICT)
+    {
+	dict_iterator_T iter;
+	typval_T	*value;
+
+	if (tv->vval.v_dict == NULL
+				   || tv->vval.v_dict->dv_hashtab.ht_used == 0)
+	    return &t_dict_empty;
+
+	// Use the type of the first value, it is the most specific.
+	dict_iterate_start(tv, &iter);
+	dict_iterate_next(&iter, &value);
+	member_type = typval2type(value, type_gap);
+	return get_dict_type(member_type, type_gap);
+    }
+
+    if (tv->v_type == VAR_FUNC || tv->v_type == VAR_PARTIAL)
+    {
+	char_u	*name = NULL;
+	ufunc_T *ufunc = NULL;
+
+	if (tv->v_type == VAR_PARTIAL)
+	{
+	    if (tv->vval.v_partial->pt_func != NULL)
+		ufunc = tv->vval.v_partial->pt_func;
+	    else
+		name = tv->vval.v_partial->pt_name;
+	}
+	else
+	    name = tv->vval.v_string;
+	if (name != NULL)
+	    // TODO: how about a builtin function?
+	    ufunc = find_func(name, FALSE, NULL);
+	if (ufunc != NULL)
+	{
+	    // May need to get the argument types from default values by
+	    // compiling the function.
+	    if (ufunc->uf_def_status == UF_TO_BE_COMPILED
+			    && compile_def_function(ufunc, TRUE, NULL) == FAIL)
+		return NULL;
+	    if (ufunc->uf_func_type != NULL)
+		return ufunc->uf_func_type;
+	}
+    }
+
+    actual = alloc_type(type_gap);
+    if (actual == NULL)
+	return NULL;
+    actual->tt_type = tv->v_type;
+    actual->tt_member = &t_any;
+
+    return actual;
+}
+
+/*
+ * Get a type_T for a typval_T, used for v: variables.
+ * "type_list" is used to temporarily create types in.
+ */
+    type_T *
+typval2type_vimvar(typval_T *tv, garray_T *type_gap)
+{
+    if (tv->v_type == VAR_LIST)  // e.g. for v:oldfiles
+	return &t_list_string;
+    if (tv->v_type == VAR_DICT)  // e.g. for v:completed_item
+	return &t_dict_any;
+    return typval2type(tv, type_gap);
+}
+
+
+/*
+ * Return FAIL if "expected" and "actual" don't match.
+ */
+    int
+check_typval_type(type_T *expected, typval_T *actual_tv)
+{
+    garray_T	type_list;
+    type_T	*actual_type;
+    int		res = FAIL;
+
+    ga_init2(&type_list, sizeof(type_T *), 10);
+    actual_type = typval2type(actual_tv, &type_list);
+    if (actual_type != NULL)
+	res = check_type(expected, actual_type, TRUE);
+    clear_type_list(&type_list);
+    return res;
+}
+
+    void
+type_mismatch(type_T *expected, type_T *actual)
+{
+    char *tofree1, *tofree2;
+
+    semsg(_("E1013: type mismatch, expected %s but got %s"),
+		   type_name(expected, &tofree1), type_name(actual, &tofree2));
+    vim_free(tofree1);
+    vim_free(tofree2);
+}
+
+    void
+arg_type_mismatch(type_T *expected, type_T *actual, int argidx)
+{
+    char *tofree1, *tofree2;
+
+    semsg(_("E1013: argument %d: type mismatch, expected %s but got %s"),
+	    argidx,
+	    type_name(expected, &tofree1), type_name(actual, &tofree2));
+    vim_free(tofree1);
+    vim_free(tofree2);
+}
+
+/*
+ * Check if the expected and actual types match.
+ * Does not allow for assigning "any" to a specific type.
+ */
+    int
+check_type(type_T *expected, type_T *actual, int give_msg)
+{
+    int ret = OK;
+
+    // When expected is "unknown" we accept any actual type.
+    // When expected is "any" we accept any actual type except "void".
+    if (expected->tt_type != VAR_UNKNOWN
+	    && !(expected->tt_type == VAR_ANY && actual->tt_type != VAR_VOID))
+
+    {
+	if (expected->tt_type != actual->tt_type)
+	{
+	    if (give_msg)
+		type_mismatch(expected, actual);
+	    return FAIL;
+	}
+	if (expected->tt_type == VAR_DICT || expected->tt_type == VAR_LIST)
+	{
+	    // "unknown" is used for an empty list or dict
+	    if (actual->tt_member != &t_unknown)
+		ret = check_type(expected->tt_member, actual->tt_member, FALSE);
+	}
+	else if (expected->tt_type == VAR_FUNC)
+	{
+	    if (expected->tt_member != &t_unknown)
+		ret = check_type(expected->tt_member, actual->tt_member, FALSE);
+	    if (ret == OK && expected->tt_argcount != -1
+		    && (actual->tt_argcount < expected->tt_min_argcount
+			|| actual->tt_argcount > expected->tt_argcount))
+		    ret = FAIL;
+	    if (expected->tt_args != NULL && actual->tt_args != NULL)
+	    {
+		int i;
+
+		for (i = 0; i < expected->tt_argcount; ++i)
+		    // Allow for using "any" argument type, lambda's have them.
+		    if (actual->tt_args[i] != &t_any && check_type(
+			       expected->tt_args[i], actual->tt_args[i], FALSE)
+								       == FAIL)
+		    {
+			ret = FAIL;
+			break;
+		    }
+	    }
+	}
+	if (ret == FAIL && give_msg)
+	    type_mismatch(expected, actual);
+    }
+    return ret;
+}
+
+/*
+ * Skip over a type definition and return a pointer to just after it.
+ * When "optional" is TRUE then a leading "?" is accepted.
+ */
+    char_u *
+skip_type(char_u *start, int optional)
+{
+    char_u *p = start;
+
+    if (optional && *p == '?')
+	++p;
+    while (ASCII_ISALNUM(*p) || *p == '_')
+	++p;
+
+    // Skip over "<type>"; this is permissive about white space.
+    if (*skipwhite(p) == '<')
+    {
+	p = skipwhite(p);
+	p = skip_type(skipwhite(p + 1), FALSE);
+	p = skipwhite(p);
+	if (*p == '>')
+	    ++p;
+    }
+    else if ((*p == '(' || (*p == ':' && VIM_ISWHITE(p[1])))
+					     && STRNCMP("func", start, 4) == 0)
+    {
+	if (*p == '(')
+	{
+	    // handle func(args): type
+	    ++p;
+	    while (*p != ')' && *p != NUL)
+	    {
+		char_u *sp = p;
+
+		if (STRNCMP(p, "...", 3) == 0)
+		    p += 3;
+		p = skip_type(p, TRUE);
+		if (p == sp)
+		    return p;  // syntax error
+		if (*p == ',')
+		    p = skipwhite(p + 1);
+	    }
+	    if (*p == ')')
+	    {
+		if (p[1] == ':')
+		    p = skip_type(skipwhite(p + 2), FALSE);
+		else
+		    ++p;
+	    }
+	}
+	else
+	{
+	    // handle func: return_type
+	    p = skip_type(skipwhite(p + 1), FALSE);
+	}
+    }
+
+    return p;
+}
+
+/*
+ * Parse the member type: "<type>" and return "type" with the member set.
+ * Use "type_gap" if a new type needs to be added.
+ * Returns NULL in case of failure.
+ */
+    static type_T *
+parse_type_member(char_u **arg, type_T *type, garray_T *type_gap)
+{
+    type_T  *member_type;
+    int	    prev_called_emsg = called_emsg;
+
+    if (**arg != '<')
+    {
+	if (*skipwhite(*arg) == '<')
+	    semsg(_(e_no_white_before), "<");
+	else
+	    emsg(_("E1008: Missing <type>"));
+	return type;
+    }
+    *arg = skipwhite(*arg + 1);
+
+    member_type = parse_type(arg, type_gap);
+
+    *arg = skipwhite(*arg);
+    if (**arg != '>' && called_emsg == prev_called_emsg)
+    {
+	emsg(_("E1009: Missing > after type"));
+	return type;
+    }
+    ++*arg;
+
+    if (type->tt_type == VAR_LIST)
+	return get_list_type(member_type, type_gap);
+    return get_dict_type(member_type, type_gap);
+}
+
+/*
+ * Parse a type at "arg" and advance over it.
+ * Return &t_any for failure.
+ */
+    type_T *
+parse_type(char_u **arg, garray_T *type_gap)
+{
+    char_u  *p = *arg;
+    size_t  len;
+
+    // skip over the first word
+    while (ASCII_ISALNUM(*p) || *p == '_')
+	++p;
+    len = p - *arg;
+
+    switch (**arg)
+    {
+	case 'a':
+	    if (len == 3 && STRNCMP(*arg, "any", len) == 0)
+	    {
+		*arg += len;
+		return &t_any;
+	    }
+	    break;
+	case 'b':
+	    if (len == 4 && STRNCMP(*arg, "bool", len) == 0)
+	    {
+		*arg += len;
+		return &t_bool;
+	    }
+	    if (len == 4 && STRNCMP(*arg, "blob", len) == 0)
+	    {
+		*arg += len;
+		return &t_blob;
+	    }
+	    break;
+	case 'c':
+	    if (len == 7 && STRNCMP(*arg, "channel", len) == 0)
+	    {
+		*arg += len;
+		return &t_channel;
+	    }
+	    break;
+	case 'd':
+	    if (len == 4 && STRNCMP(*arg, "dict", len) == 0)
+	    {
+		*arg += len;
+		return parse_type_member(arg, &t_dict_any, type_gap);
+	    }
+	    break;
+	case 'f':
+	    if (len == 5 && STRNCMP(*arg, "float", len) == 0)
+	    {
+#ifdef FEAT_FLOAT
+		*arg += len;
+		return &t_float;
+#else
+		emsg(_("E1076: This Vim is not compiled with float support"));
+		return &t_any;
+#endif
+	    }
+	    if (len == 4 && STRNCMP(*arg, "func", len) == 0)
+	    {
+		type_T  *type;
+		type_T  *ret_type = &t_unknown;
+		int	argcount = -1;
+		int	flags = 0;
+		int	first_optional = -1;
+		type_T	*arg_type[MAX_FUNC_ARGS + 1];
+
+		// func({type}, ...{type}): {type}
+		*arg += len;
+		if (**arg == '(')
+		{
+		    // "func" may or may not return a value, "func()" does
+		    // not return a value.
+		    ret_type = &t_void;
+
+		    p = ++*arg;
+		    argcount = 0;
+		    while (*p != NUL && *p != ')')
+		    {
+			if (*p == '?')
+			{
+			    if (first_optional == -1)
+				first_optional = argcount;
+			    ++p;
+			}
+			else if (STRNCMP(p, "...", 3) == 0)
+			{
+			    flags |= TTFLAG_VARARGS;
+			    p += 3;
+			}
+			else if (first_optional != -1)
+			{
+			    emsg(_("E1007: mandatory argument after optional argument"));
+			    return &t_any;
+			}
+
+			arg_type[argcount++] = parse_type(&p, type_gap);
+
+			// Nothing comes after "...{type}".
+			if (flags & TTFLAG_VARARGS)
+			    break;
+
+			if (*p != ',' && *skipwhite(p) == ',')
+			{
+			    semsg(_(e_no_white_before), ",");
+			    return &t_any;
+			}
+			if (*p == ',')
+			{
+			    ++p;
+			    if (!VIM_ISWHITE(*p))
+			    {
+				semsg(_(e_white_after), ",");
+				return &t_any;
+			    }
+			}
+			p = skipwhite(p);
+			if (argcount == MAX_FUNC_ARGS)
+			{
+			    emsg(_("E740: Too many argument types"));
+			    return &t_any;
+			}
+		    }
+
+		    p = skipwhite(p);
+		    if (*p != ')')
+		    {
+			emsg(_(e_missing_close));
+			return &t_any;
+		    }
+		    *arg = p + 1;
+		}
+		if (**arg == ':')
+		{
+		    // parse return type
+		    ++*arg;
+		    if (!VIM_ISWHITE(**arg))
+			semsg(_(e_white_after), ":");
+		    *arg = skipwhite(*arg);
+		    ret_type = parse_type(arg, type_gap);
+		}
+		if (flags == 0 && first_optional == -1 && argcount <= 0)
+		    type = get_func_type(ret_type, argcount, type_gap);
+		else
+		{
+		    type = alloc_func_type(ret_type, argcount, type_gap);
+		    type->tt_flags = flags;
+		    if (argcount > 0)
+		    {
+			type->tt_argcount = argcount;
+			type->tt_min_argcount = first_optional == -1
+						   ? argcount : first_optional;
+			if (func_type_add_arg_types(type, argcount,
+							     type_gap) == FAIL)
+			    return &t_any;
+			mch_memmove(type->tt_args, arg_type,
+						  sizeof(type_T *) * argcount);
+		    }
+		}
+		return type;
+	    }
+	    break;
+	case 'j':
+	    if (len == 3 && STRNCMP(*arg, "job", len) == 0)
+	    {
+		*arg += len;
+		return &t_job;
+	    }
+	    break;
+	case 'l':
+	    if (len == 4 && STRNCMP(*arg, "list", len) == 0)
+	    {
+		*arg += len;
+		return parse_type_member(arg, &t_list_any, type_gap);
+	    }
+	    break;
+	case 'n':
+	    if (len == 6 && STRNCMP(*arg, "number", len) == 0)
+	    {
+		*arg += len;
+		return &t_number;
+	    }
+	    break;
+	case 's':
+	    if (len == 6 && STRNCMP(*arg, "string", len) == 0)
+	    {
+		*arg += len;
+		return &t_string;
+	    }
+	    break;
+	case 'v':
+	    if (len == 4 && STRNCMP(*arg, "void", len) == 0)
+	    {
+		*arg += len;
+		return &t_void;
+	    }
+	    break;
+    }
+
+    semsg(_("E1010: Type not recognized: %s"), *arg);
+    return &t_any;
+}
+
+/*
+ * Check if "type1" and "type2" are exactly the same.
+ */
+    static int
+equal_type(type_T *type1, type_T *type2)
+{
+    int i;
+
+    if (type1->tt_type != type2->tt_type)
+	return FALSE;
+    switch (type1->tt_type)
+    {
+	case VAR_UNKNOWN:
+	case VAR_ANY:
+	case VAR_VOID:
+	case VAR_SPECIAL:
+	case VAR_BOOL:
+	case VAR_NUMBER:
+	case VAR_FLOAT:
+	case VAR_STRING:
+	case VAR_BLOB:
+	case VAR_JOB:
+	case VAR_CHANNEL:
+	    break;  // not composite is always OK
+	case VAR_LIST:
+	case VAR_DICT:
+	    return equal_type(type1->tt_member, type2->tt_member);
+	case VAR_FUNC:
+	case VAR_PARTIAL:
+	    if (!equal_type(type1->tt_member, type2->tt_member)
+		    || type1->tt_argcount != type2->tt_argcount)
+		return FALSE;
+	    if (type1->tt_argcount < 0
+			   || type1->tt_args == NULL || type2->tt_args == NULL)
+		return TRUE;
+	    for (i = 0; i < type1->tt_argcount; ++i)
+		if (!equal_type(type1->tt_args[i], type2->tt_args[i]))
+		    return FALSE;
+	    return TRUE;
+    }
+    return TRUE;
+}
+
+/*
+ * Find the common type of "type1" and "type2" and put it in "dest".
+ * "type2" and "dest" may be the same.
+ */
+    void
+common_type(type_T *type1, type_T *type2, type_T **dest, garray_T *type_gap)
+{
+    if (equal_type(type1, type2))
+    {
+	*dest = type1;
+	return;
+    }
+
+    if (type1->tt_type == type2->tt_type)
+    {
+	if (type1->tt_type == VAR_LIST || type2->tt_type == VAR_DICT)
+	{
+	    type_T *common;
+
+	    common_type(type1->tt_member, type2->tt_member, &common, type_gap);
+	    if (type1->tt_type == VAR_LIST)
+		*dest = get_list_type(common, type_gap);
+	    else
+		*dest = get_dict_type(common, type_gap);
+	    return;
+	}
+	if (type1->tt_type == VAR_FUNC)
+	{
+	    type_T *common;
+
+	    common_type(type1->tt_member, type2->tt_member, &common, type_gap);
+	    if (type1->tt_argcount == type2->tt_argcount
+						    && type1->tt_argcount >= 0)
+	    {
+		int argcount = type1->tt_argcount;
+		int i;
+
+		*dest = alloc_func_type(common, argcount, type_gap);
+		if (type1->tt_args != NULL && type2->tt_args != NULL)
+		{
+		    if (func_type_add_arg_types(*dest, argcount,
+							     type_gap) == OK)
+			for (i = 0; i < argcount; ++i)
+			    common_type(type1->tt_args[i], type2->tt_args[i],
+					       &(*dest)->tt_args[i], type_gap);
+		}
+	    }
+	    else
+		*dest = alloc_func_type(common, -1, type_gap);
+	    return;
+	}
+    }
+
+    *dest = &t_any;
+}
+
+    char *
+vartype_name(vartype_T type)
+{
+    switch (type)
+    {
+	case VAR_UNKNOWN: break;
+	case VAR_ANY: return "any";
+	case VAR_VOID: return "void";
+	case VAR_SPECIAL: return "special";
+	case VAR_BOOL: return "bool";
+	case VAR_NUMBER: return "number";
+	case VAR_FLOAT: return "float";
+	case VAR_STRING: return "string";
+	case VAR_BLOB: return "blob";
+	case VAR_JOB: return "job";
+	case VAR_CHANNEL: return "channel";
+	case VAR_LIST: return "list";
+	case VAR_DICT: return "dict";
+
+	case VAR_FUNC:
+	case VAR_PARTIAL: return "func";
+    }
+    return "unknown";
+}
+
+/*
+ * Return the name of a type.
+ * The result may be in allocated memory, in which case "tofree" is set.
+ */
+    char *
+type_name(type_T *type, char **tofree)
+{
+    char *name = vartype_name(type->tt_type);
+
+    *tofree = NULL;
+    if (type->tt_type == VAR_LIST || type->tt_type == VAR_DICT)
+    {
+	char *member_free;
+	char *member_name = type_name(type->tt_member, &member_free);
+	size_t len;
+
+	len = STRLEN(name) + STRLEN(member_name) + 3;
+	*tofree = alloc(len);
+	if (*tofree != NULL)
+	{
+	    vim_snprintf(*tofree, len, "%s<%s>", name, member_name);
+	    vim_free(member_free);
+	    return *tofree;
+	}
+    }
+    if (type->tt_type == VAR_FUNC)
+    {
+	garray_T    ga;
+	int	    i;
+	int	    varargs = (type->tt_flags & TTFLAG_VARARGS) ? 1 : 0;
+
+	ga_init2(&ga, 1, 100);
+	if (ga_grow(&ga, 20) == FAIL)
+	    return "[unknown]";
+	*tofree = ga.ga_data;
+	STRCPY(ga.ga_data, "func(");
+	ga.ga_len += 5;
+
+	for (i = 0; i < type->tt_argcount; ++i)
+	{
+	    char *arg_free;
+	    char *arg_type;
+	    int  len;
+
+	    if (type->tt_args == NULL)
+		arg_type = "[unknown]";
+	    else
+		arg_type = type_name(type->tt_args[i], &arg_free);
+	    if (i > 0)
+	    {
+		STRCPY((char *)ga.ga_data + ga.ga_len, ", ");
+		ga.ga_len += 2;
+	    }
+	    len = (int)STRLEN(arg_type);
+	    if (ga_grow(&ga, len + 8) == FAIL)
+	    {
+		vim_free(arg_free);
+		return "[unknown]";
+	    }
+	    *tofree = ga.ga_data;
+	    if (varargs && i == type->tt_argcount - 1)
+	    {
+		STRCPY((char *)ga.ga_data + ga.ga_len, "...");
+		ga.ga_len += 3;
+	    }
+	    else if (i >= type->tt_min_argcount)
+		*((char *)ga.ga_data + ga.ga_len++) = '?';
+	    STRCPY((char *)ga.ga_data + ga.ga_len, arg_type);
+	    ga.ga_len += len;
+	    vim_free(arg_free);
+	}
+
+	if (type->tt_member == &t_void)
+	    STRCPY((char *)ga.ga_data + ga.ga_len, ")");
+	else
+	{
+	    char *ret_free;
+	    char *ret_name = type_name(type->tt_member, &ret_free);
+	    int  len;
+
+	    len = (int)STRLEN(ret_name) + 4;
+	    if (ga_grow(&ga, len) == FAIL)
+	    {
+		vim_free(ret_free);
+		return "[unknown]";
+	    }
+	    *tofree = ga.ga_data;
+	    STRCPY((char *)ga.ga_data + ga.ga_len, "): ");
+	    STRCPY((char *)ga.ga_data + ga.ga_len + 3, ret_name);
+	    vim_free(ret_free);
+	}
+	return ga.ga_data;
+    }
+
+    return name;
+}
+
+
+#endif // FEAT_EVAL