xo-reader: wip: parsing lambda expressions [wip, non-functional]

This commit is contained in:
Roland Conybeare 2024-08-17 01:09:17 -04:00
commit 0841fd7dbd
10 changed files with 289 additions and 5 deletions

View file

@ -1,11 +1,90 @@
/* @file lambda_xs.cpp */
#include "lambda_xs.hpp"
#include "expect_formal_arglist_xs.hpp"
#include "expect_expr_xs.hpp"
#include "xo/expression/Lambda.hpp"
namespace xo {
using xo::ast::Lambda;
namespace scm {
std::unique_ptr<lambda_xs>
lambda_xs::make() {
return std::make_unique<lambda_xs>(lambda_xs());
}
lambda_xs::lambda_xs() {}
void
lambda_xs::on_lambda_token(const token_type & tk,
exprstatestack * p_stack,
rp<Expression> * p_emit_expr)
{
if (lmxs_type_ == lambdastatetype::lm_0) {
this->lmxs_type_ = lambdastatetype::lm_1;
p_stack->push_exprstate(expect_formal_arglist_xs::make());
return;
}
exprstate::on_lambda_token(tk,
p_stack,
p_emit_expr);
}
void
lambda_xs::on_formal_arglist(const std::vector<rp<Variable>> & argl,
exprstatestack * p_stack,
rp<Expression> * p_emit_expr)
{
if (lmxs_type_ == lambdastatetype::lm_1) {
this->lmxs_type_ = lambdastatetype::lm_2;
this->argl_ = argl;
p_stack->push_exprstate(expect_expr_xs::expect_rhs_expression());
return;
}
exprstate::on_formal_arglist(argl,
p_stack,
p_emit_expr);
}
void
lambda_xs::on_expr(ref::brw<Expression> expr,
exprstatestack * p_stack,
rp<Expression> * p_emit_expr)
{
if (lmxs_type_ == lambdastatetype::lm_2) {
this->lmxs_type_ = lambdastatetype::lm_3;
this->body_ = expr.promote();
return;
}
exprstate::on_expr(expr, p_stack, p_emit_expr);
}
void
lambda_xs::on_semicolon_token(const token_type & tk,
exprstatestack * p_stack,
rp<Expression> * p_emit_expr)
{
if (lmxs_type_ == lambdastatetype::lm_3) {
/* done! */
std::unique_ptr<exprstate> self = p_stack->pop_exprstate();
std::string name = "fixmename";
rp<Lambda> lm = Lambda::make(name, argl_, body_);
p_stack->top_exprstate().on_expr(lm, p_stack, p_emit_expr);
p_stack->top_exprstate().on_semicolon_token(tk, p_stack, p_emit_expr);
return;
}
exprstate::on_semicolon_token(tk, p_stack, p_emit_expr);
}
} /*namespace scm*/
} /*namespace xo*/