xo-reader2: more work on apply expressions [WIP]

This commit is contained in:
Roland Conybeare 2026-02-11 20:25:24 -05:00
commit e0ab3c5927
6 changed files with 238 additions and 61 deletions

View file

@ -46,8 +46,8 @@ namespace xo {
apply_0,
apply_1,
apply_2,
apply_3,
apply_2, // rename -> apply_2a
apply_3, // rename -> apply_2b
N
};
@ -81,7 +81,8 @@ namespace xo {
* that we parse f before parser knows that it will be
* followed by leftparen
**/
explicit DApplySsm(obj<AExpression> fn_expr);
explicit DApplySsm(obj<AExpression> fn_expr,
DArray * args);
/** create instance using memory from @p parser_mm.
* with function to be called supplied by @p fn_expr.
@ -103,9 +104,8 @@ namespace xo {
**/
static void start(obj<AExpression> fnex,
ParserStateMachine * p_psm);
///@}
/** @defgroup scm-applyssm-access methods **/
/** @defgroup scm-applyssm-access-methods access methods **/
///@{
/** identify this nested state machine **/
@ -114,6 +114,16 @@ namespace xo {
/** current internal state **/
applyexprstatetype applystate() const noexcept { return applystate_; }
///@}
/** @defgroup scm-applyssm-methods general methods **/
///@{
/** handle leftparen token @p tk for this ssm,
* with overall parser state in @p p_psm
**/
void on_leftparen_token(const Token & tk,
ParserStateMachine * p_psm);
///@}
/** @defgroup ssm-applyssm-facet syntaxstatemachine facet methods **/
///@{
@ -124,6 +134,12 @@ namespace xo {
/** mnemonic for expected remaining syntax for current parsing state **/
std::string_view get_expect_str() const noexcept;
/** update this apply-ssm for incoming token @p tk,
* with overall parsing state in @p p_psm
**/
void on_token(const Token & tk,
ParserStateMachine * p_psm);
///@}
#ifdef NOT_YET
@ -133,14 +149,9 @@ namespace xo {
virtual void on_comma_token(const token_type & tk,
parserstatemachine * p_psm) override;
virtual void on_leftparen_token(const token_type & tk,
parserstatemachine * p_psm) override;
virtual void on_rightparen_token(const token_type & tk,
parserstatemachine * p_psm) override;
virtual void print(std::ostream & os) const override;
virtual bool pretty_print(const print::ppindentinfo & ppii) const final override;
private:
static std::unique_ptr<apply_xs> make();
#endif
@ -158,10 +169,14 @@ namespace xo {
applyexprstatetype applystate_ = applyexprstatetype::apply_0;
/** evaluates to function to be invoked **/
obj<AExpression> fn_expr_;
#ifdef NOT_YET
/** evaluates to the arguments to pass to @ref fn_ **/
std::vector<rp<Expression>> args_expr_v_;
#endif
/** args_expr_v_[i] evaluates to the i'th argument to call.
* Not using flexible array here since we don't know size at
* construction time
*
* (though could revisit + realloc this DApplySsm instance in
* place to optimize)
**/
DArray * args_expr_v_ = nullptr;
};
} /*namespace scm */

View file

@ -137,6 +137,8 @@ namespace xo {
/** handle leftparen token @p tk. Overall parser state in @p p_psm **/
void on_leftparen_token(const Token & tk,
ParserStateMachine * p_psm);
void on_rightparen_token(const Token & tk,
ParserStateMachine * p_psm);
void on_symbol_token(const Token & tk,
ParserStateMachine * p_psm);

View file

@ -4,6 +4,7 @@
**/
#include "ApplySsm.hpp"
#include "ExpectExprSsm.hpp"
#include <xo/reflectutil/typeseq.hpp>
//#include "parserstatemachine.hpp"
@ -39,13 +40,18 @@ namespace xo {
// ----- DApplySsm -----
DApplySsm::DApplySsm(obj<AExpression> fn_expr)
: applystate_{applyexprstatetype::apply_0},
fn_expr_{fn_expr}
DApplySsm::DApplySsm(applyexprstatetype applystate,
obj<AExpression> fn_expr,
DArray * args)
: applystate_{applystate},
fn_expr_{fn_expr},
arg_expr_v_{args}
{
if (fn_expr) {
this->applystate_ = applyexprstatetype::apply_1;
}
assert(args->empty());
}
DApplySsm *
@ -55,10 +61,21 @@ namespace xo {
void * mem = mm.alloc(typeseq::id<DApplySsm>(),
sizeof(DApplySsm));
// TODO: revisit if we use flexible array for
// arguments
/* allocate room for 8 arguments (during parsing)
* will reallocate to expand if needed.
*
* See similar code in DExpectFormalArglistSsm::_make
*/
DArray * args = DArray::empty(mm, 8);
return new (mem) DApplySsm(fn_expr);
applyexprstatetype applystate
= (fn_expr
? applyexprstatetype::apply_1
: applyexprstatetype::apply_0);
// TODO: revisit if we decide to use flexible array for arguments
return new (mem) DApplySsm(applystate, fn_expr, args);
}
void
@ -98,6 +115,124 @@ namespace xo {
return "?expect";
}
void
DApplySsm::on_token(const Token & tk,
ParserStateMachine * p_psm)
{
scope log(XO_DEBUG(p_psm->debug_flag()), xtag("tk", tk));
switch (tk.tk_type()) {
case tokentype::tk_leftparen:
this->on_leftparen_token(tk, p_psm);
return;
case tokentype::tk_symbol:
case tokentype::tk_def:
case tokentype::tk_if:
case tokentype::tk_then:
case tokentype::tk_else:
case tokentype::tk_semicolon:
case tokentype::tk_colon:
case tokentype::tk_singleassign:
case tokentype::tk_string:
case tokentype::tk_f64:
case tokentype::tk_i64:
case tokentype::tk_bool:
case tokentype::tk_invalid:
case tokentype::tk_rightparen:
case tokentype::tk_leftbracket:
case tokentype::tk_rightbracket:
case tokentype::tk_leftbrace:
case tokentype::tk_rightbrace:
case tokentype::tk_leftangle:
case tokentype::tk_rightangle:
case tokentype::tk_lessequal:
case tokentype::tk_greatequal:
case tokentype::tk_dot:
case tokentype::tk_comma:
case tokentype::tk_doublecolon:
case tokentype::tk_assign:
case tokentype::tk_yields:
case tokentype::tk_plus:
case tokentype::tk_minus:
case tokentype::tk_star:
case tokentype::tk_slash:
case tokentype::tk_cmpeq:
case tokentype::tk_cmpne:
case tokentype::tk_type:
case tokentype::tk_lambda:
case tokentype::tk_let:
case tokentype::tk_in:
case tokentype::tk_end:
case tokentype::N:
break;
}
Super::on_token(tk, p_psm);
}
void
DApplySsm::on_leftparen_token(const Token & tk,
ParserStateMachine * p_psm)
{
if (applystate_ == applyexprstatetype::apply_1) {
this->applystate_ = applyexprstatetype::apply_2;
DExpectExprSsm::start(p_psm);
return;
}
Super::on_token(tk, p_psm);
}
void
DApplySsm::on_parsed_expression_with_token(obj<AExpression> expr,
const Token & tk)
{
if (applystate_ == applyexprstatetype::apply_2) {
if (args_expr_v_->size() == args_expr_v_->capacity()) {
// need to expand .args_expr_v_ capacity.
// Could use DArena checkpoint to redo this in place,
// since argument array must be on the top of the stack.
obj<AAllocator,DArena> mm(&(p_psm->parser_alloc()));
DArray * argv_2x = DArray::empty(mm, 2 * args_expr_v_->capacity());
for (DArray::size_type i = 0, n = arg_expr_v_->size(); i < n; ++i) {
argv_2x->push_back((*argv_)[i]);
}
this->args_expr_v_ = argv_2x;
}
if (args_expr_v_->size() < args_expr_v_->capacity()) {
args_expr_v_->push_back(expr);
}
if (tk.tk_type() == tokentype::tk_rightparen) {
// expression completes apply
// TODO: assemble apply expression..
assert(false);
}
if ((tk.tk_type() == tokentype::tk_comma)
|| (tk.tk_type() == tokentype::tk_rightparen)) {
// do stuff,
//return;
}
// complain
assert(false);
}
Super::on_parsed_expression_with_token(expr, tk);
}
#ifdef NOT_YET
void
apply_xs::on_expr(bp<Expression> expr,
@ -154,25 +289,6 @@ namespace xo {
}
}
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)
@ -214,26 +330,6 @@ namespace xo {
refrtag("fn_expr", fn_expr, fn_expr_present));
}
#ifdef NOT_YET
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*/

View file

@ -182,7 +182,8 @@ namespace xo {
if (fastate_ == formalarglstatetype::argl_1a) {
this->fastate_ = formalarglstatetype::argl_1b;
TypeRef typeref = TypeRef::dwim(TypeRef::prefix_type::from_chars("formal"), param_type);
TypeRef typeref
= TypeRef::dwim(TypeRef::prefix_type::from_chars("formal"), param_type);
DVariable * var = DVariable::make(p_psm->expr_alloc(),
param_name,

View file

@ -267,11 +267,14 @@ namespace xo {
this->on_leftparen_token(tk, p_psm);
return;
case tokentype::tk_rightparen:
this->on_rightparen_token(tk, p_psm);
return;
// all the not-yet handled cases
case tokentype::tk_invalid:
case tokentype::tk_def:
case tokentype::tk_if:
case tokentype::tk_rightparen:
case tokentype::tk_leftbracket:
case tokentype::tk_rightbracket:
case tokentype::tk_leftbrace:
@ -937,6 +940,9 @@ namespace xo {
this->lhs_ = obj<AExpression>();
DApplySsm::start(fn_expr, p_psm);
// + send leftparen to just-pushed apply
p_psm->on_token(tk);
return;
}
@ -986,7 +992,40 @@ namespace xo {
this->illegal_input_on_token(c_self_name, tk, exp, p_psm);
}
#endif
void
DProgressSsm::on_rightparen_token(const Token & tk,
ParserStateMachine * p_psm)
{
/* note: implementation parallels .on_semicolon_token() */
scope log(XO_DEBUG(p_psm->debug_flag()));
/* stack may be something like:
*
* [0] DProgressSsm
* [1] DExpectExprSsm
* [2] DApplySsm
*
* where we want rightparen to resolve in [2] DApplySsm,
* after triggering completion of [0] and [1]
*/
auto expr = this->assemble_expr(p_psm);
if (expr) {
/* 1. popping self from parser stack.. */
p_psm->pop_ssm();
/* 2. report parsed subexpr to parent ssm, along with the triggering rightparen **/
p_psm->on_parsed_expression_with_token(expr, tk);
return;
}
Super::on_token(tk, p_psm);
}
#ifdef NOT_YET
void
progress_xs::on_rightparen_token(const token_type & tk,
parserstatemachine * p_psm)

View file

@ -1204,6 +1204,30 @@ namespace xo {
REQUIRE(!result.is_error());
REQUIRE(result.is_incomplete());
}
{
auto & result = parser.on_token(Token::i64_token("13"));
log && log("after i64(13) token:");
log && log(xtag("parser", &parser));
log && log(xtag("result", result));
REQUIRE(parser.has_incomplete_expr() == true);
REQUIRE(!result.is_error());
REQUIRE(result.is_incomplete());
}
{
auto & result = parser.on_token(Token::rightparen_token());
log && log("after rightparen token:");
log && log(xtag("parser", &parser));
log && log(xtag("result", result));
REQUIRE(parser.has_incomplete_expr() == true);
REQUIRE(!result.is_error());
REQUIRE(result.is_incomplete());
}
}
} /*namespace ut*/
} /*namespace xo*/