roland/xo-alloc
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

xo-reader xo-expression: nested lambdas working properly + docs

Browse source
This commit is contained in:
Roland Conybeare 2025-07-06 14:13:44 -05:00
commit 699ee5d38e
41 changed files with 736 additions and 137 deletions
Download patch file Download diff file Expand all files Collapse all files

70
xo-reader/src/reader/let1_xs.cpp
View file

@ -17,20 +17,18 @@ namespace xo {
using Apply = xo::ast::Apply;
using Lambda = xo::ast::Lambda;
using LambdaAccess = xo::ast::LambdaAccess;
using Environment = xo::ast::Environment;
using LocalEnv = xo::ast::LocalEnv;
using Variable = xo::ast::Variable;
namespace {
std::string gensym() {
return "genanotherxx";
}
}
namespace scm {
std::unique_ptr<let1_xs>
let1_xs::make(std::string lhs_name,
rp<LocalEnv> local_env,
rp<Expression> rhs)
{
return std::make_unique<let1_xs>(let1_xs(std::move(lhs_name),
std::move(local_env),
std::move(rhs)));
}
@ -39,7 +37,16 @@ namespace xo {
const rp<Expression> & rhs,
parserstatemachine * p_psm)
{
p_psm->push_exprstate(let1_xs::make(lhs_name, rhs));
rp<Environment> parent_env = p_psm->top_envframe().promote();
rp<Variable> var1 = Variable::make(lhs_name, rhs->valuetype());
rp<LocalEnv> let_env = LocalEnv::make1(var1, parent_env);
p_psm->push_envframe(let_env);
// TODO: stash let_env in let1_xs, then pick up directly in .on_rightbrace_token()
// still have to push here so vars can find it
//
p_psm->push_exprstate(let1_xs::make(lhs_name, let_env, rhs));
expect_expr_xs::start(true /*allow_defs*/,
true /*cxl_on_rightbrace*/,
@ -47,9 +54,11 @@ namespace xo {
}
let1_xs::let1_xs(std::string lhs_name,
rp<LocalEnv> local_env,
rp<Expression> rhs)
: exprstate(),
: exprstate(exprstatetype::let1expr),
lhs_name_{std::move(lhs_name)},
local_env_{std::move(local_env)},
rhs_{std::move(rhs)}
{}
@ -63,7 +72,8 @@ namespace xo {
bp<DefineExpr> def_expr = DefineExpr::from(expr);
if (def_expr) {
/** nested_start: control returns via
/** starting a nested let here:
* control returns via
* .on_expr(x)
* with x something like:
* Apply(Lambda(gensym(),
@ -85,6 +95,32 @@ namespace xo {
}
}
void
let1_xs::on_expr_with_semicolon(bp<Expression> expr,
parserstatemachine * p_psm)
{
/* same as on_expr(), since we only use let1_xs inside a block { .. }
* This means final ';' is unnecessary
*/
constexpr bool c_debug_flag = true;
scope log(XO_DEBUG(c_debug_flag));
bp<DefineExpr> def_expr = DefineExpr::from(expr);
if (def_expr) {
let1_xs::start(def_expr->lhs_name(),
def_expr->rhs(),
p_psm);
} else {
this->expr_v_.push_back(expr.promote());
expect_expr_xs::start(true /*allow_defs*/,
true /*cxl_on_rightbvrace*/,
p_psm);
}
}
void
let1_xs::on_rightbrace_token(const token_type & tk,
parserstatemachine * p_psm)
@ -93,13 +129,19 @@ namespace xo {
auto expr = Sequence::make(this->expr_v_);
std::string argname = gensym();
/* top env frame was established by let1_xs::start();
* now unwind it
*/
p_psm->pop_envframe();
std::string lambda_name = Variable::gensym("let1");
rp<Environment> parent_env = p_psm->top_envframe().promote();
rp<Expression> lambda
= Lambda::make(this->lhs_name_,
{Variable::make(argname,
this->rhs_->valuetype())},
expr);
= Lambda::make_from_env(lambda_name,
local_env_,
expr);
rp<Expression> result
= Apply::make(lambda, {this->rhs_});