94 lines
3.1 KiB
C++
94 lines
3.1 KiB
C++
/** @file DGlobalEnv.hpp
|
|
*
|
|
* @author Roland Conybeare, Feb 2026
|
|
**/
|
|
|
|
#pragma once
|
|
|
|
#include <xo/expression2/DGlobalSymtab.hpp>
|
|
#include <xo/object2/DArray.hpp>
|
|
|
|
namespace xo {
|
|
namespace scm {
|
|
|
|
/** @brief runtime bindings for global variabels
|
|
*
|
|
* Implementation here uses a DArenaHashMap to hold <key,value> pairs.
|
|
* The hash map has its own memory outside GC space.
|
|
* Keys are DUniqueStrings, also outside GC space.
|
|
* Values are regular gc-aware objects, generally will be in GC space.
|
|
*
|
|
* We need collector to traverse all the values in a global env
|
|
* on each cycle. Arrange that by having DGlobalEnv itself
|
|
* in GC space.
|
|
*
|
|
**/
|
|
class DGlobalEnv {
|
|
public:
|
|
using TypeDescr = xo::reflect::TypeDescr;
|
|
using ACollector = xo::mm::ACollector;
|
|
using AAllocator = xo::mm::AAllocator;
|
|
using AGCObject = xo::mm::AGCObject;
|
|
using MemorySizeVisitor = xo::mm::MemorySizeVisitor;
|
|
using ppindentinfo = xo::print::ppindentinfo;
|
|
using size_type = std::uint32_t;
|
|
|
|
public:
|
|
/** @defgroup scm-globalenv-ctors constructors **/
|
|
///@{
|
|
|
|
DGlobalEnv(DGlobalSymtab * symtab, DArray * values);
|
|
|
|
static DGlobalEnv * _make(obj<AAllocator> mm,
|
|
DGlobalSymtab * symtab);
|
|
|
|
|
|
///@}
|
|
/** @defgroup scm-globalenv-methods methods **/
|
|
///@{
|
|
|
|
/** symbol-table size. Is the number of distinct global variables **/
|
|
size_type n_vars() const noexcept { return symtab_->n_vars(); }
|
|
|
|
/** lookup current value associated with binding @p ix **/
|
|
obj<AGCObject> lookup_value(Binding ix) const noexcept;
|
|
|
|
/** assign value associated with binding @p to @p x.
|
|
* If need to expand size of this env, use memory from @p mm
|
|
**/
|
|
void assign_value(obj<AAllocator> mm, Binding ix, obj<AGCObject> x);
|
|
|
|
/** create/establish global for symbol @p sym with resolved type @p td
|
|
* and associate with @p value.
|
|
**/
|
|
DVariable * _upsert_value(obj<AAllocator> mm,
|
|
const DUniqueString * sym,
|
|
TypeDescr td,
|
|
obj<AGCObject> value);
|
|
|
|
///@}
|
|
/** @defgroup scm-globalenv-gcobject-facet **/
|
|
///@{
|
|
|
|
std::size_t shallow_size() const noexcept;
|
|
DGlobalEnv * shallow_move(obj<ACollector> gc) noexcept;
|
|
std::size_t forward_children(obj<ACollector> gc) noexcept;
|
|
|
|
///@}
|
|
/** @defgroup scm-globalenv-printable-facet **/
|
|
///@{
|
|
|
|
bool pretty(const ppindentinfo & ppii) const;
|
|
|
|
///@}
|
|
|
|
private:
|
|
|
|
/** symbol table assigns a unique index for each symbol **/
|
|
DGlobalSymtab * symtab_;
|
|
|
|
/** value for a symbol S will be in values_[symtab->lookup_binding(S)] **/
|
|
DArray * values_ = nullptr;
|
|
};
|
|
}
|
|
}
|