bool expr_qualify(pass_opt_t* opt, ast_t** astp)
{
// Left is a postfix expression, right is a typeargs.
ast_t* ast = *astp;
AST_GET_CHILDREN(ast, left, right);
ast_t* type = ast_type(left);
assert(ast_id(right) == TK_TYPEARGS);
if(is_typecheck_error(type))
return false;
switch(ast_id(left))
{
case TK_TYPEREF:
{
// Qualify the type.
assert(ast_id(type) == TK_NOMINAL);
// If the type isn't polymorphic or the type is already qualified,
// sugar .apply().
ast_t* def = names_def(opt, type);
ast_t* typeparams = ast_childidx(def, 1);
if((ast_id(typeparams) == TK_NONE) ||
(ast_id(ast_childidx(type, 2)) != TK_NONE))
{
if(!expr_nominal(opt, &type))
return false;
break;
}
type = ast_dup(type);
ast_t* typeargs = ast_childidx(type, 2);
ast_replace(&typeargs, right);
ast_settype(ast, type);
ast_setid(ast, TK_TYPEREF);
return expr_typeref(opt, astp);
}
case TK_NEWREF:
case TK_NEWBEREF:
case TK_BEREF:
case TK_FUNREF:
case TK_NEWAPP:
case TK_BEAPP:
case TK_FUNAPP:
{
// Qualify the function.
assert(ast_id(type) == TK_FUNTYPE);
ast_t* typeparams = ast_childidx(type, 1);
if(!reify_defaults(typeparams, right, true, opt))
return false;
if(!check_constraints(left, typeparams, right, true, opt))
return false;
type = reify(type, typeparams, right, opt);
typeparams = ast_childidx(type, 1);
ast_replace(&typeparams, ast_from(typeparams, TK_NONE));
ast_settype(ast, type);
ast_setid(ast, ast_id(left));
ast_inheritflags(ast);
return true;
}
default: {}
}
// Sugar .apply()
ast_t* dot = ast_from(left, TK_DOT);
ast_add(dot, ast_from_string(left, "apply"));
ast_swap(left, dot);
ast_add(dot, left);
if(!expr_dot(opt, &dot))
return false;
return expr_qualify(opt, astp);
}
bool expr_this(pass_opt_t* opt, ast_t* ast)
{
typecheck_t* t = &opt->check;
if(t->frame->def_arg != NULL)
{
ast_error(ast, "can't reference 'this' in a default argument");
return false;
}
sym_status_t status;
ast_get(ast, stringtab("this"), &status);
if(status == SYM_CONSUMED)
{
ast_error(ast, "can't use a consumed 'this' in an expression");
return false;
}
assert(status == SYM_NONE);
token_id cap = cap_for_this(t);
if(!cap_sendable(cap) && (t->frame->recover != NULL))
cap = TK_TAG;
bool make_arrow = false;
if(cap == TK_BOX)
{
cap = TK_REF;
make_arrow = true;
}
ast_t* type = type_for_this(opt, ast, cap, TK_NONE, false);
if(make_arrow)
{
BUILD(arrow, ast, NODE(TK_ARROW, NODE(TK_THISTYPE) TREE(type)));
type = arrow;
}
// Get the nominal type, which may be the right side of an arrow type.
ast_t* nominal;
bool arrow;
if(ast_id(type) == TK_NOMINAL)
{
nominal = type;
arrow = false;
} else {
nominal = ast_childidx(type, 1);
arrow = true;
}
ast_t* typeargs = ast_childidx(nominal, 2);
ast_t* typearg = ast_child(typeargs);
while(typearg != NULL)
{
if(!expr_nominal(opt, &typearg))
{
ast_error(ast, "couldn't create a type for 'this'");
ast_free(type);
return false;
}
typearg = ast_sibling(typearg);
}
if(!expr_nominal(opt, &nominal))
{
ast_error(ast, "couldn't create a type for 'this'");
ast_free(type);
return false;
}
if(arrow)
type = ast_parent(nominal);
else
type = nominal;
ast_settype(ast, type);
return true;
}
bool expr_this(pass_opt_t* opt, ast_t* ast)
{
typecheck_t* t = &opt->check;
if(t->frame->def_arg != NULL)
{
ast_error(opt->check.errors, ast,
"can't reference 'this' in a default argument");
return false;
}
sym_status_t status;
ast_get(ast, stringtab("this"), &status);
if(status == SYM_CONSUMED)
{
ast_error(opt->check.errors, ast,
"can't use a consumed 'this' in an expression");
return false;
}
assert(status == SYM_NONE);
token_id cap = cap_for_this(t);
if(!cap_sendable(cap) && (t->frame->recover != NULL))
{
ast_t* parent = ast_parent(ast);
if(ast_id(parent) != TK_DOT)
cap = TK_TAG;
}
bool make_arrow = false;
if(cap == TK_BOX)
{
cap = TK_REF;
make_arrow = true;
}
ast_t* type = type_for_this(opt, ast, cap, TK_NONE, false);
if(make_arrow)
{
BUILD(arrow, ast, NODE(TK_ARROW, NODE(TK_THISTYPE) TREE(type)));
type = arrow;
}
// Get the nominal type, which may be the right side of an arrow type.
ast_t* nominal;
bool arrow;
if(ast_id(type) == TK_NOMINAL)
{
nominal = type;
arrow = false;
} else {
nominal = ast_childidx(type, 1);
arrow = true;
}
ast_t* typeargs = ast_childidx(nominal, 2);
ast_t* typearg = ast_child(typeargs);
while(typearg != NULL)
{
if(!expr_nominal(opt, &typearg))
{
ast_error(opt->check.errors, ast, "couldn't create a type for 'this'");
ast_free(type);
return false;
}
typearg = ast_sibling(typearg);
}
if(!expr_nominal(opt, &nominal))
{
ast_error(opt->check.errors, ast, "couldn't create a type for 'this'");
ast_free(type);
return false;
}
// Unless this is a field lookup, treat an incomplete `this` as a tag.
ast_t* parent = ast_parent(ast);
bool incomplete_ok = false;
if((ast_id(parent) == TK_DOT) && (ast_child(parent) == ast))
{
ast_t* right = ast_sibling(ast);
assert(ast_id(right) == TK_ID);
ast_t* find = lookup_try(opt, ast, nominal, ast_name(right));
if(find != NULL)
{
switch(ast_id(find))
{
case TK_FVAR:
case TK_FLET:
case TK_EMBED:
incomplete_ok = true;
break;
default: {}
}
}
}
if(!incomplete_ok && is_this_incomplete(t, ast))
{
ast_t* tag_type = set_cap_and_ephemeral(nominal, TK_TAG, TK_NONE);
ast_replace(&nominal, tag_type);
}
if(arrow)
type = ast_parent(nominal);
else
type = nominal;
ast_settype(ast, type);
return true;
}
bool expr_typeref(pass_opt_t* opt, ast_t** astp)
{
ast_t* ast = *astp;
assert(ast_id(ast) == TK_TYPEREF);
ast_t* type = ast_type(ast);
if(is_typecheck_error(type))
return false;
switch(ast_id(ast_parent(ast)))
{
case TK_QUALIFY:
// Doesn't have to be valid yet.
break;
case TK_DOT:
// Has to be valid.
if(!expr_nominal(opt, &type))
{
ast_settype(ast, ast_from(type, TK_ERRORTYPE));
ast_free_unattached(type);
return false;
}
break;
case TK_CALL:
{
// Has to be valid.
if(!expr_nominal(opt, &type))
{
ast_settype(ast, ast_from(type, TK_ERRORTYPE));
ast_free_unattached(type);
return false;
}
// Transform to a default constructor.
ast_t* dot = ast_from(ast, TK_DOT);
ast_add(dot, ast_from_string(ast, "create"));
ast_swap(ast, dot);
*astp = dot;
ast_add(dot, ast);
if(!expr_dot(opt, astp))
{
ast_settype(ast, ast_from(type, TK_ERRORTYPE));
ast_free_unattached(type);
return false;
}
ast_t* ast = *astp;
// If the default constructor has no parameters, transform to an apply
// call.
if((ast_id(ast) == TK_NEWREF) || (ast_id(ast) == TK_NEWBEREF))
{
type = ast_type(ast);
if(is_typecheck_error(type))
return false;
assert(ast_id(type) == TK_FUNTYPE);
AST_GET_CHILDREN(type, cap, typeparams, params, result);
if(ast_id(params) == TK_NONE)
{
// Add a call node.
ast_t* call = ast_from(ast, TK_CALL);
ast_add(call, ast_from(call, TK_NONE)); // Named
ast_add(call, ast_from(call, TK_NONE)); // Positional
ast_swap(ast, call);
ast_append(call, ast);
if(!expr_call(opt, &call))
{
ast_settype(ast, ast_from(type, TK_ERRORTYPE));
ast_free_unattached(type);
return false;
}
// Add a dot node.
ast_t* apply = ast_from(call, TK_DOT);
ast_add(apply, ast_from_string(call, "apply"));
ast_swap(call, apply);
ast_add(apply, call);
if(!expr_dot(opt, &apply))
{
ast_settype(ast, ast_from(type, TK_ERRORTYPE));
ast_free_unattached(type);
return false;
}
}
}
return true;
}
default:
{
// Has to be valid.
if(!expr_nominal(opt, &type))
{
ast_settype(ast, ast_from(type, TK_ERRORTYPE));
ast_free_unattached(type);
return false;
}
// Transform to a default constructor.
ast_t* dot = ast_from(ast, TK_DOT);
ast_add(dot, ast_from_string(ast, "create"));
ast_swap(ast, dot);
ast_add(dot, ast);
// Call the default constructor with no arguments.
ast_t* call = ast_from(ast, TK_CALL);
ast_swap(dot, call);
ast_add(call, dot); // Receiver comes last.
ast_add(call, ast_from(ast, TK_NONE)); // Named args.
ast_add(call, ast_from(ast, TK_NONE)); // Positional args.
*astp = call;
if(!expr_dot(opt, &dot))
{
ast_settype(ast, ast_from(type, TK_ERRORTYPE));
ast_free_unattached(type);
return false;
}
if(!expr_call(opt, astp))
{
ast_settype(ast, ast_from(type, TK_ERRORTYPE));
ast_free_unattached(type);
return false;
}
break;
}
}
return true;
}
ast_result_t pass_expr(ast_t** astp, pass_opt_t* options)
{
typecheck_t* t = &options->check;
ast_t* ast = *astp;
bool r = true;
switch(ast_id(ast))
{
case TK_NOMINAL: r = expr_nominal(options, astp); break;
case TK_FVAR:
case TK_FLET:
case TK_PARAM: r = expr_field(options, ast); break;
case TK_NEW:
case TK_BE:
case TK_FUN: r = expr_fun(options, ast); break;
case TK_SEQ: r = expr_seq(ast); break;
case TK_VAR:
case TK_LET: r = expr_local(t, ast); break;
case TK_BREAK: r = expr_break(t, ast); break;
case TK_CONTINUE: r = expr_continue(t, ast); break;
case TK_RETURN: r = expr_return(options, ast); break;
case TK_IS:
case TK_ISNT: r = expr_identity(options, ast); break;
case TK_ASSIGN: r = expr_assign(options, ast); break;
case TK_CONSUME: r = expr_consume(t, ast); break;
case TK_RECOVER: r = expr_recover(ast); break;
case TK_DOT: r = expr_dot(options, astp); break;
case TK_TILDE: r = expr_tilde(options, astp); break;
case TK_QUALIFY: r = expr_qualify(options, astp); break;
case TK_CALL: r = expr_call(options, astp); break;
case TK_IF: r = expr_if(options, ast); break;
case TK_WHILE: r = expr_while(options, ast); break;
case TK_REPEAT: r = expr_repeat(options, ast); break;
case TK_TRY_NO_CHECK:
case TK_TRY: r = expr_try(options, ast); break;
case TK_MATCH: r = expr_match(options, ast); break;
case TK_CASES: r = expr_cases(ast); break;
case TK_CASE: r = expr_case(options, ast); break;
case TK_TUPLE: r = expr_tuple(ast); break;
case TK_ARRAY: r = expr_array(options, astp); break;
case TK_REFERENCE: r = expr_reference(options, astp); break;
case TK_THIS: r = expr_this(options, ast); break;
case TK_TRUE:
case TK_FALSE: r = expr_literal(options, ast, "Bool"); break;
case TK_ERROR: r = expr_error(ast); break;
case TK_COMPILER_INTRINSIC:
r = expr_compiler_intrinsic(t, ast); break;
case TK_POSITIONALARGS:
case TK_NAMEDARGS:
case TK_NAMEDARG:
case TK_UPDATEARG: ast_inheritflags(ast); break;
case TK_AMP: r = expr_addressof(options, ast); break;
case TK_DONTCARE: r = expr_dontcare(ast); break;
case TK_INT:
// Integer literals can be integers or floats
make_literal_type(ast);
break;
case TK_FLOAT:
make_literal_type(ast);
break;
case TK_STRING:
if(ast_id(ast_parent(ast)) == TK_PACKAGE)
return AST_OK;
r = expr_literal(options, ast, "String");
break;
case TK_FFICALL:
return expr_ffi(options, ast);
default: {}
}
if(!r)
{
assert(get_error_count() > 0);
return AST_ERROR;
}
// Can't use ast here, it might have changed
symtab_t* symtab = ast_get_symtab(*astp);
if(symtab != NULL && !symtab_check_all_defined(symtab))
return AST_ERROR;
return AST_OK;
}