xo-reader2: DApplySsm for apply expressions [WIP]

This commit is contained in:
Roland Conybeare 2026-02-11 16:02:41 -05:00
commit 40e1fb531d
7 changed files with 402 additions and 6 deletions

221
src/reader2/DApplySsm.cpp Normal file
View file

@ -0,0 +1,221 @@
/** @file DApplySsm.cpp
*
* @author Roland Conybeare, Feb 2026
**/
#include "DApplySsm.hpp"
#include <xo/reflectutil/typeseq.hpp>
//#include "parserstatemachine.hpp"
//#include "expect_expr_xs.hpp"
namespace xo {
using xo::reflect::typeseq;
namespace scm {
// ----- applyexprstatetype -----
const char *
applyexprstatetype_descr(applyexprstatetype x) {
switch (x) {
case applyexprstatetype::invalid: return "invalid";
case applyexprstatetype::apply_0: return "apply_0";
case applyexprstatetype::apply_1: return "apply_1";
case applyexprstatetype::apply_2: return "apply_2";
case applyexprstatetype::apply_3: return "apply_3";
case applyexprstatetype::N: break;
}
return "???applyexprstatetype";
}
std::ostream &
operator<<(std::ostream & os, applyexprstatetype x) {
os << applyexprstatetype_descr(x);
return os;
}
// ----- DApplySsm -----
DApplySsm::DApplySsm(obj<AExpression> fn_expr)
: applystate_{applyexprstatetype::apply_0},
fn_expr_{fn_expr}
{
if (fn_expr) {
this->applystate_ = applyexprstatetype::apply_1;
}
}
DApplySsm *
DApplySsm::make(DArena & mm,
obj<AExpression> fn_expr)
{
void * mem = mm.alloc(typeseq::id<DApplySsm>(),
sizeof(DApplySsm));
// TODO: revisit if we use flexible array for
// arguments
return new (mem) DApplySsm(fn_expr);
}
#ifdef NOT_YET
void
apply_xs::start(rp<Expression> fn_expr,
parserstatemachine * p_psm)
{
scope log(XO_DEBUG(p_psm->debug_flag()));
p_psm->push_exprstate(apply_xs::make());
p_psm->top_exprstate().on_expr(fn_expr.get(), p_psm);
p_psm->top_exprstate().on_leftparen_token(token_type::leftparen(), p_psm);
}
#endif
syntaxstatetype
DApplySsm::ssm_type() const noexcept {
return syntaxstatetype::apply;
}
std::string_view
DApplySsm::get_expect_str() const noexcept
{
switch(applystate_) {
case applyexprstatetype::invalid: return "invalid";
case applyexprstatetype::apply_0: return "expr";
case applyexprstatetype::apply_1: return "lparen";
case applyexprstatetype::apply_2: return "expr";
case applyexprstatetype::apply_3: return "comma|rparen";
case applyexprstatetype::N: break;
}
return "?expect";
}
#ifdef NOT_YET
void
apply_xs::on_expr(bp<Expression> expr,
parserstatemachine * p_psm)
{
scope log(XO_DEBUG(p_psm->debug_flag()));
switch (applyxs_type_) {
case applyexprstatetype::invalid:
case applyexprstatetype::n_applyexprstatetype:
// unreachable
break;
case applyexprstatetype::apply_0:
log && log("stash fn -> new state apply_1");
this->fn_expr_ = expr.promote();
this->applyxs_type_ = applyexprstatetype::apply_1;
return;
case applyexprstatetype::apply_1:
log && log("error: was expecting lparen");
// error, expecting lparen
break;
case applyexprstatetype::apply_2:
log && log(xtag("expr", expr), xtag("do", "stash expr -> new state apply_3"));
this->args_expr_v_.push_back(expr.promote());
this->applyxs_type_ = applyexprstatetype::apply_3;
return;
case applyexprstatetype::apply_3:
// error, expecting comma|rparen
break;
}
/* control here --implies-> error state */
constexpr const char * c_self_name = "apply_xs::on_expr";
const char * exp = this->get_expect_str();
this->illegal_input_on_expr(c_self_name, expr, exp, p_psm);
}
void
apply_xs::on_comma_token(const token_type & tk,
parserstatemachine * p_psm)
{
scope log(XO_DEBUG(p_psm->debug_flag()));
if (this->applyxs_type_ == applyexprstatetype::apply_3) {
this->applyxs_type_ = applyexprstatetype::apply_2;
expect_expr_xs::start(p_psm);
} else {
constexpr const char * c_self_name = "apply_xs::on_comma_token";
const char * exp = this->get_expect_str();
this->illegal_input_on_token(c_self_name, tk, exp, p_psm);
}
}
void
apply_xs::on_leftparen_token(const token_type & tk,
parserstatemachine * p_psm)
{
scope log(XO_DEBUG(p_psm->debug_flag()));
log && log("applyxs_type", applyxs_type_);
if (this->applyxs_type_ == applyexprstatetype::apply_1) {
this->applyxs_type_ = applyexprstatetype::apply_2;
expect_expr_xs::start(p_psm);
} else {
constexpr const char * c_self_name = "apply_xs::on_leftparen_token";
const char * exp = this->get_expect_str();
this->illegal_input_on_token(c_self_name, tk, exp, p_psm);
}
}
void
apply_xs::on_rightparen_token(const token_type & tk,
parserstatemachine * p_psm)
{
scope log(XO_DEBUG(p_psm->debug_flag()));
log && log("applyxs_type", applyxs_type_);
if (this->applyxs_type_ == applyexprstatetype::apply_3) {
/* (done) state */
log("apply complete -> pop + send expr");
rp<Apply> apply_expr = Apply::make(this->fn_expr_, this->args_expr_v_);
std::unique_ptr<exprstate> self = p_psm->pop_exprstate();
p_psm->top_exprstate().on_expr(apply_expr, p_psm);
return;
}
constexpr const char * c_self_name = "apply_xs::on_rightparen_token";
const char * exp = this->get_expect_str();
this->illegal_input_on_token(c_self_name, tk, exp, p_psm);
}
void
apply_xs::print(std::ostream & os) const
{
os << "<apply_xs"
<< xtag("this", (void*)this)
<< xtag("applyxs_type", applyxs_type_);
os << ">";
}
bool
apply_xs::pretty_print(const xo::print::ppindentinfo & ppii) const
{
return ppii.pps()->pretty_struct(ppii, "apply_xs",
refrtag("applyxs_type", applyxs_type_),
refrtag("fn_expr", fn_expr_),
refrtag("args_expr_v", args_expr_v_));
}
#endif
} /*namespace scm*/
} /*namespace xo*/
/* end DApplySsm.cpp */