Roland Conybeare
d14f119a37
Helps streamline DX1Collector in xo-gc/. Want both forward and verify entry points for the same representation.
91 lines
3.1 KiB
C++
91 lines
3.1 KiB
C++
/* file DExpectSymbolSsm.hpp
|
|
*
|
|
* author: Roland Conybeare, Aug 2024
|
|
*/
|
|
|
|
#pragma once
|
|
|
|
#include "DSyntaxStateMachine.hpp"
|
|
#include "syntaxstatetype.hpp"
|
|
#include <xo/indentlog/print/ppindentinfo.hpp>
|
|
#include <xo/facet/obj.hpp>
|
|
|
|
namespace xo {
|
|
namespace scm {
|
|
/** @class DExpectSymbolSsm
|
|
* @brief state machine to expect + capture a symbol
|
|
*
|
|
* For example:
|
|
* - lhs in a define-expression
|
|
**/
|
|
class DExpectSymbolSsm : public DSyntaxStateMachine<DExpectSymbolSsm> {
|
|
public:
|
|
using Super = DSyntaxStateMachine<DExpectSymbolSsm>;
|
|
using AGCObjectVisitor = xo::mm::AGCObjectVisitor;
|
|
using VisitReason = xo::mm::VisitReason;
|
|
using DArena = xo::mm::DArena;
|
|
using TypeDescr = xo::reflect::TypeDescr;
|
|
using ppindentinfo = xo::print::ppindentinfo;
|
|
|
|
public:
|
|
DExpectSymbolSsm();
|
|
|
|
/** create instance using memory from @p parser_mm **/
|
|
static DExpectSymbolSsm * _make(DArena & parser_mm);
|
|
|
|
/** create fop referring to new DExpectSymbolSsm **/
|
|
static obj<ASyntaxStateMachine,DExpectSymbolSsm> make(DArena & parser_mm);
|
|
|
|
/** start nested parser expecting a symbol,
|
|
* on top of parser state machine @p p_psm.
|
|
* On success will deliver symbol by invoking
|
|
* .on_symbol(sym, p_psm)
|
|
* to the state machine on top of the stack
|
|
* as of when this start() method invoked
|
|
**/
|
|
static void start(ParserStateMachine * p_psm);
|
|
|
|
/** update state for this syntax on incoming token @p tk,
|
|
* with overall parser state in @p p_psm
|
|
**/
|
|
static void on_symbol_token(const Token & tk,
|
|
ParserStateMachine * p_psm);
|
|
|
|
static const char * ssm_classname() { return "DExpectSymbolSsm"; }
|
|
|
|
/** @defgroup scm-expectsymbol-ssm-facet syntaxstatemachine facet methods **/
|
|
///@{
|
|
|
|
/** identifies the ssm implemented here **/
|
|
syntaxstatetype ssm_type() const noexcept;
|
|
|
|
/** text describing expected/allowed input to this ssm in current state.
|
|
* Intended to drive error mesages
|
|
**/
|
|
std::string_view get_expect_str() const noexcept;
|
|
|
|
/** operate state machine for this syntax on incoming token @p tk
|
|
* with overall parser state in @p p_psm
|
|
**/
|
|
void on_token(const Token & tk,
|
|
ParserStateMachine * p_psm);
|
|
|
|
///@}
|
|
/** @defgroup scm-expectsymbol-printable-facet printable facet methods **/
|
|
///@{
|
|
|
|
bool pretty(const ppindentinfo & ppii) const;
|
|
|
|
///@}
|
|
/** @defgroup scm-expectsymbolssm-gc-support gc support methods **/
|
|
///@{
|
|
|
|
/** gc support: visit gc-aware child pointers **/
|
|
void visit_gco_children(VisitReason reason, obj<AGCObjectVisitor> gc) noexcept;
|
|
|
|
///@}
|
|
};
|
|
} /*namespace scm*/
|
|
} /*namespace xo*/
|
|
|
|
/* end DExpectSymbolSsm.hpp */
|