bool flatten_arrows(ast_t** astp, bool errors)
{
ast_t* ast = *astp;
ast_t* node_type = ast_type(ast);
if(node_type != NULL)
{
if(!flatten_arrows(&node_type, errors))
return false;
}
if(ast_id(ast) == TK_ARROW)
{
AST_GET_CHILDREN(ast, left, right);
ast_t* flat;
if(!flatten_arrows(&right, errors))
return false;
if((ast_id(left) == TK_BOXTYPE) && (ast_id(right) != TK_ARROW))
flat = viewpoint_cap(TK_BOX, TK_NONE, right);
else
flat = viewpoint_type(left, right);
if(flat == NULL)
{
if(errors)
ast_error(ast, "can't flatten arrow type");
return false;
}
ast_replace(astp, flat);
return true;
}
ast_t* child = ast_child(ast);
while(child != NULL)
{
if(!flatten_arrows(&child, errors))
return false;
child = ast_sibling(child);
}
return true;
}
static ast_t* lookup_nominal(typecheck_t* t, ast_t* from, ast_t* orig,
ast_t* type, const char* name, bool errors)
{
assert(ast_id(type) == TK_NOMINAL);
ast_t* def = (ast_t*)ast_data(type);
ast_t* type_name = ast_child(def);
ast_t* find = ast_get(def, name, NULL);
if(find != NULL)
{
switch(ast_id(find))
{
case TK_FVAR:
case TK_FLET:
case TK_NEW:
case TK_BE:
case TK_FUN:
break;
default:
find = NULL;
}
}
if(find == NULL)
{
if(errors)
ast_error(from, "couldn't find '%s' in '%s'", name, ast_name(type_name));
return NULL;
}
if((name[0] == '_') && (from != NULL) && (t != NULL))
{
switch(ast_id(find))
{
case TK_FVAR:
case TK_FLET:
if(t->frame->type != def)
{
if(errors)
{
ast_error(from,
"can't lookup private fields from outside the type");
}
return NULL;
}
break;
case TK_NEW:
case TK_BE:
case TK_FUN:
{
if(ast_nearest(def, TK_PACKAGE) != t->frame->package)
{
if(errors)
{
ast_error(from,
"can't lookup private methods from outside the package");
}
return NULL;
}
break;
}
default:
assert(0);
return NULL;
}
if(!strcmp(name, "_final"))
{
switch(ast_id(find))
{
case TK_NEW:
case TK_BE:
case TK_FUN:
if(errors)
ast_error(from, "can't lookup a _final function");
return NULL;
default: {}
}
}
}
ast_t* typeparams = ast_sibling(type_name);
ast_t* typeargs = ast_childidx(type, 2);
find = ast_dup(find);
orig = ast_dup(orig);
replace_thistype(&find, orig);
ast_free_unattached(orig);
ast_t* r_find = reify(from, find, typeparams, typeargs);
if(r_find != find)
{
ast_free_unattached(find);
find = r_find;
}
if((find != NULL) && !flatten_arrows(&find, errors))
{
if(errors)
ast_error(from, "can't look this up on a tag");
ast_free_unattached(find);
return NULL;
}
return find;
}
