use erg_common::fresh::fresh_varname;
use erg_common::traits::{Locational, Stream};
use erg_common::Str;
use erg_common::{enum_unwrap, get_hash, log, set};
use crate::ast::{
Accessor, Args, Array, ArrayComprehension, ArrayTypeSpec, ArrayWithLength, BinOp, Block, Call,
ClassAttr, ClassAttrs, ClassDef, ConstExpr, DataPack, Def, DefBody, DefId, Dict, Dummy, Expr,
Identifier, KeyValue, KwArg, Lambda, LambdaSignature, Literal, Methods, MixedRecord, Module,
NonDefaultParamSignature, NormalArray, NormalDict, NormalRecord, NormalSet, NormalTuple,
ParamPattern, ParamRecordAttr, Params, PatchDef, PosArg, ReDef, Record, RecordAttrOrIdent,
RecordAttrs, Set as astSet, SetWithLength, Signature, SubrSignature, Tuple, TupleTypeSpec,
TypeAppArgs, TypeAppArgsKind, TypeBoundSpecs, TypeSpec, TypeSpecWithOp, UnaryOp, VarName,
VarPattern, VarRecordAttr, VarSignature, VisModifierSpec,
};
use crate::token::{Token, TokenKind, COLON, DOT};
#[derive(Debug, Clone, PartialEq, Eq)]
enum BufIndex<'i> {
Array(usize),
Tuple(usize),
Record(&'i Identifier),
}
#[derive(Debug)]
pub struct Desugarer {
}
impl Desugarer {
pub fn new() -> Desugarer {
Self {
}
}
pub fn desugar(&mut self, module: Module) -> Module {
log!(info "the desugaring process has started.");
let module = self.desugar_multiple_pattern_def(module);
let module = self.desugar_pattern_in_module(module);
let module = Self::desugar_shortened_record(module);
let module = Self::desugar_acc(module);
log!(info "AST (desugared):\n{module}");
log!(info "the desugaring process has completed.");
module
}
pub fn desugar_simple_expr(expr: Expr) -> Expr {
let expr = Self::rec_desugar_shortened_record(expr);
let expr = Self::rec_desugar_lambda_pattern(&mut Desugarer {}, expr);
Self::rec_desugar_acc(expr)
}
fn desugar_all_chunks(module: Module, desugar: impl Fn(Expr) -> Expr) -> Module {
module.into_iter().map(desugar).collect()
}
fn desugar_args(mut desugar: impl FnMut(Expr) -> Expr, args: Args) -> Args {
let (pos_args, var_args, kw_args, paren) = args.deconstruct();
let pos_args = pos_args
.into_iter()
.map(|arg| PosArg::new(desugar(arg.expr)))
.collect();
let var_args = var_args.map(|arg| PosArg::new(desugar(arg.expr)));
let kw_args = kw_args
.into_iter()
.map(|arg| {
KwArg::new(arg.keyword, arg.t_spec, desugar(arg.expr)) })
.collect();
Args::new(pos_args, var_args, kw_args, paren)
}
fn perform_desugar_acc(mut desugar: impl FnMut(Expr) -> Expr, acc: Accessor) -> Accessor {
match acc {
Accessor::Ident(ident) => Accessor::Ident(ident),
Accessor::Attr(attr) => desugar(*attr.obj).attr(attr.ident),
Accessor::TupleAttr(tup) => {
let obj = desugar(*tup.obj);
obj.tuple_attr(tup.index)
}
Accessor::Subscr(sub) => {
let obj = desugar(*sub.obj);
let index = desugar(*sub.index);
obj.subscr(index, sub.r_sqbr)
}
Accessor::TypeApp(tapp) => {
let obj = desugar(*tapp.obj);
let args = match tapp.type_args.args {
TypeAppArgsKind::Args(args) => {
TypeAppArgsKind::Args(Self::desugar_args(desugar, args))
}
other => other,
};
let type_args =
TypeAppArgs::new(tapp.type_args.l_vbar, args, tapp.type_args.r_vbar);
obj.type_app(type_args)
}
}
}
fn perform_desugar(mut desugar: impl FnMut(Expr) -> Expr, expr: Expr) -> Expr {
match expr {
Expr::Literal(_) => expr,
Expr::Record(record) => match record {
Record::Normal(rec) => {
let mut new_attrs = vec![];
for attr in rec.attrs {
new_attrs.push(enum_unwrap!(desugar(Expr::Def(attr)), Expr::Def));
}
Expr::Record(Record::Normal(NormalRecord::new(
rec.l_brace,
rec.r_brace,
RecordAttrs::new(new_attrs),
)))
}
Record::Mixed(mixed) => {
let mut new_attrs = vec![];
for attr in mixed.attrs {
match attr {
RecordAttrOrIdent::Attr(attr) => {
let attr = RecordAttrOrIdent::Attr(enum_unwrap!(
desugar(Expr::Def(attr)),
Expr::Def
));
new_attrs.push(attr);
}
RecordAttrOrIdent::Ident(ident) => {
new_attrs.push(RecordAttrOrIdent::Ident(ident));
}
}
}
Expr::Record(Record::Mixed(MixedRecord::new(
mixed.l_brace,
mixed.r_brace,
new_attrs,
)))
}
},
Expr::DataPack(pack) => {
let class = desugar(*pack.class);
let args = enum_unwrap!(desugar(Expr::Record(pack.args)), Expr::Record);
Expr::DataPack(DataPack::new(class, pack.connector, args))
}
Expr::Array(array) => match array {
Array::Normal(arr) => {
let (elems, ..) = arr.elems.deconstruct();
let elems = elems
.into_iter()
.map(|elem| PosArg::new(desugar(elem.expr)))
.collect();
let elems = Args::pos_only(elems, None);
let arr = NormalArray::new(arr.l_sqbr, arr.r_sqbr, elems);
Expr::Array(Array::Normal(arr))
}
Array::WithLength(arr) => {
let elem = PosArg::new(desugar(arr.elem.expr));
let len = desugar(*arr.len);
let arr = ArrayWithLength::new(arr.l_sqbr, arr.r_sqbr, elem, len);
Expr::Array(Array::WithLength(arr))
}
Array::Comprehension(arr) => {
let elem = desugar(*arr.elem);
let generators = arr
.generators
.into_iter()
.map(|(ident, gen)| (ident, desugar(gen)))
.collect();
let guards = arr.guards.into_iter().map(desugar).collect();
let arr =
ArrayComprehension::new(arr.l_sqbr, arr.r_sqbr, elem, generators, guards);
Expr::Array(Array::Comprehension(arr))
}
},
Expr::Tuple(tuple) => match tuple {
Tuple::Normal(tup) => {
let (elems, _, _, paren) = tup.elems.deconstruct();
let elems = elems
.into_iter()
.map(|elem| PosArg::new(desugar(elem.expr)))
.collect();
let new_tup = Args::pos_only(elems, paren);
let tup = NormalTuple::new(new_tup);
Expr::Tuple(Tuple::Normal(tup))
}
},
Expr::Set(set) => match set {
astSet::Normal(set) => {
let (elems, ..) = set.elems.deconstruct();
let elems = elems
.into_iter()
.map(|elem| PosArg::new(desugar(elem.expr)))
.collect();
let elems = Args::pos_only(elems, None);
let set = NormalSet::new(set.l_brace, set.r_brace, elems);
Expr::Set(astSet::Normal(set))
}
astSet::WithLength(set) => {
let elem = PosArg::new(desugar(set.elem.expr));
let len = desugar(*set.len);
let set = SetWithLength::new(set.l_brace, set.r_brace, elem, len);
Expr::Set(astSet::WithLength(set))
}
},
Expr::Dict(dict) => match dict {
Dict::Normal(dic) => {
let new_kvs = dic
.kvs
.into_iter()
.map(|elem| {
let key = desugar(elem.key);
let value = desugar(elem.value);
KeyValue::new(key, value)
})
.collect();
let tup = NormalDict::new(dic.l_brace, dic.r_brace, new_kvs);
Expr::Dict(Dict::Normal(tup))
}
_ => todo!("dict comprehension"),
},
Expr::BinOp(binop) => {
let mut args = binop.args.into_iter();
let lhs = desugar(*args.next().unwrap());
let rhs = desugar(*args.next().unwrap());
Expr::BinOp(BinOp::new(binop.op, lhs, rhs))
}
Expr::UnaryOp(unaryop) => {
let mut args = unaryop.args.into_iter();
let expr = desugar(*args.next().unwrap());
Expr::UnaryOp(UnaryOp::new(unaryop.op, expr))
}
Expr::Call(call) => {
let obj = desugar(*call.obj);
let args = Self::desugar_args(desugar, call.args);
Expr::Call(Call::new(obj, call.attr_name, args))
}
Expr::Def(def) => {
let mut chunks = vec![];
for chunk in def.body.block.into_iter() {
chunks.push(desugar(chunk));
}
let body = DefBody::new(def.body.op, Block::new(chunks), def.body.id);
Expr::Def(Def::new(def.sig, body))
}
Expr::ClassDef(class_def) => {
let def = enum_unwrap!(desugar(Expr::Def(class_def.def)), Expr::Def);
let methods = class_def
.methods_list
.into_iter()
.map(|method| enum_unwrap!(desugar(Expr::Methods(method)), Expr::Methods))
.collect();
Expr::ClassDef(ClassDef::new(def, methods))
}
Expr::PatchDef(class_def) => {
let def = enum_unwrap!(desugar(Expr::Def(class_def.def)), Expr::Def);
let methods = class_def
.methods_list
.into_iter()
.map(|method| enum_unwrap!(desugar(Expr::Methods(method)), Expr::Methods))
.collect();
Expr::PatchDef(PatchDef::new(def, methods))
}
Expr::ReDef(redef) => {
let expr = desugar(*redef.expr);
let attr = Self::perform_desugar_acc(desugar, redef.attr);
Expr::ReDef(ReDef::new(attr, expr))
}
Expr::Lambda(lambda) => {
let mut chunks = vec![];
for chunk in lambda.body.into_iter() {
chunks.push(desugar(chunk));
}
let body = Block::new(chunks);
Expr::Lambda(Lambda::new(lambda.sig, lambda.op, body, lambda.id))
}
Expr::TypeAscription(tasc) => {
let expr = desugar(*tasc.expr);
let t_spec_as_expr = desugar(*tasc.t_spec.t_spec_as_expr);
let t_spec =
TypeSpecWithOp::new(tasc.t_spec.op, tasc.t_spec.t_spec, t_spec_as_expr);
expr.type_asc_expr(t_spec)
}
Expr::Methods(method_defs) => {
let mut new_attrs = vec![];
for attr in method_defs.attrs.into_iter() {
let mut chunks = vec![];
match attr {
ClassAttr::Def(def) => {
for chunk in def.body.block.into_iter() {
chunks.push(desugar(chunk));
}
let body = DefBody::new(def.body.op, Block::new(chunks), def.body.id);
new_attrs.push(ClassAttr::Def(Def::new(def.sig, body)));
}
ClassAttr::Decl(decl) => {
let expr = desugar(*decl.expr);
let t_spec_as_expr = desugar(*decl.t_spec.t_spec_as_expr);
let t_spec = TypeSpecWithOp::new(
decl.t_spec.op,
decl.t_spec.t_spec,
t_spec_as_expr,
);
new_attrs.push(ClassAttr::Decl(expr.type_asc(t_spec)));
}
ClassAttr::Doc(doc) => {
new_attrs.push(ClassAttr::Doc(doc));
}
}
}
let new_attrs = ClassAttrs::from(new_attrs);
Expr::Methods(Methods::new(
method_defs.class,
*method_defs.class_as_expr,
method_defs.vis,
new_attrs,
))
}
Expr::Accessor(acc) => Expr::Accessor(Self::perform_desugar_acc(desugar, acc)),
Expr::Dummy(exprs) => {
let loc = exprs.loc;
let mut chunks = vec![];
for chunk in exprs.into_iter() {
chunks.push(desugar(chunk));
}
Expr::Dummy(Dummy::new(loc, chunks))
}
}
}
fn desugar_multiple_pattern_def(&self, module: Module) -> Module {
let mut new = Module::with_capacity(module.len());
for chunk in module.into_iter() {
match chunk {
Expr::Def(def) if def.is_subr() => {
if let Some(Expr::Def(previous)) = new.last() {
if previous.is_subr() && previous.sig.name_as_str() == def.sig.name_as_str()
{
let previous = enum_unwrap!(new.pop().unwrap(), Expr::Def);
let name = def.sig.ident().unwrap().clone();
let id = def.body.id;
let op = def.body.op.clone();
let (call, return_t_spec) = if previous.body.block.len() == 1
&& previous.body.block.first().unwrap().is_match_call()
{
self.add_arg_to_match_call(previous, def)
} else {
self.gen_match_call(previous, def)
};
let param_name = enum_unwrap!(&call.args.pos_args().iter().next().unwrap().expr, Expr::Accessor:(Accessor::Ident:(_))).inspect();
let param = VarName::new(Token::new(
TokenKind::Symbol,
param_name,
name.ln_begin().unwrap_or(1),
name.col_end().unwrap_or(0) + 1, ));
let param =
NonDefaultParamSignature::new(ParamPattern::VarName(param), None);
let params = Params::single(param);
let sig = Signature::Subr(SubrSignature::new(
set! {},
name,
TypeBoundSpecs::empty(),
params,
return_t_spec,
));
let body = DefBody::new(op, Block::new(vec![Expr::Call(call)]), id);
let def = Def::new(sig, body);
new.push(Expr::Def(def));
} else {
new.push(Expr::Def(def));
}
} else {
new.push(Expr::Def(def));
}
}
other => {
new.push(other);
}
}
}
new
}
fn add_arg_to_match_call(&self, mut previous: Def, def: Def) -> (Call, Option<TypeSpec>) {
let op = Token::from_str(TokenKind::FuncArrow, "->");
let mut call = enum_unwrap!(previous.body.block.remove(0), Expr::Call);
let sig = enum_unwrap!(def.sig, Signature::Subr);
let return_t_spec = sig.return_t_spec;
let first_arg = sig.params.non_defaults.first().unwrap();
if let Some(name) = first_arg.inspect() {
call.args.remove_pos(0);
let arg = PosArg::new(Expr::local(
name,
first_arg.ln_begin().unwrap_or(1),
first_arg.col_begin().unwrap_or(0),
));
call.args.insert_pos(0, arg);
}
let sig = LambdaSignature::new(sig.params, return_t_spec.clone(), sig.bounds);
let new_branch = Lambda::new(sig, op, def.body.block, def.body.id);
call.args.push_pos(PosArg::new(Expr::Lambda(new_branch)));
(call, return_t_spec)
}
fn gen_match_call(&self, previous: Def, def: Def) -> (Call, Option<TypeSpec>) {
let op = Token::from_str(TokenKind::FuncArrow, "->");
let sig = enum_unwrap!(previous.sig, Signature::Subr);
let match_symbol = Expr::static_local("match");
let sig = LambdaSignature::new(sig.params, sig.return_t_spec, sig.bounds);
let first_branch = Lambda::new(sig, op.clone(), previous.body.block, previous.body.id);
let sig = enum_unwrap!(def.sig, Signature::Subr);
let return_t_spec = sig.return_t_spec;
let sig = LambdaSignature::new(sig.params, return_t_spec.clone(), sig.bounds);
let second_branch = Lambda::new(sig, op, def.body.block, def.body.id);
let args = Args::pos_only(
vec![
PosArg::new(Expr::dummy_local("_")), PosArg::new(Expr::Lambda(first_branch)),
PosArg::new(Expr::Lambda(second_branch)),
],
None,
);
let call = match_symbol.call(args);
(call, return_t_spec)
}
fn _desugar_literal_pattern(&self, _mod: Module) -> Module {
todo!()
}
fn gen_buf_name_and_sig(&mut self, line: u32, t_spec: Option<TypeSpec>) -> (String, Signature) {
let buf_name = fresh_varname();
let buf_sig = Signature::Var(VarSignature::new(
VarPattern::Ident(Identifier::private_with_line(Str::rc(&buf_name), line)),
t_spec,
));
(buf_name, buf_sig)
}
fn gen_buf_nd_param(&mut self, line: u32) -> (String, ParamPattern) {
let buf_name = fresh_varname();
let pat = ParamPattern::VarName(VarName::from_str_and_line(Str::rc(&buf_name), line));
(buf_name, pat)
}
fn rec_desugar_lambda_pattern(&mut self, expr: Expr) -> Expr {
match expr {
Expr::Lambda(mut lambda) => {
let non_defaults = lambda.sig.params.non_defaults.iter_mut();
for param in non_defaults {
self.desugar_nd_param(param, &mut lambda.body);
}
lambda.body = self.desugar_pattern_in_block(lambda.body);
Expr::Lambda(lambda)
}
expr => Self::perform_desugar(|ex| self.rec_desugar_lambda_pattern(ex), expr),
}
}
fn desugar_pattern_in_module(&mut self, module: Module) -> Module {
Module::new(self.desugar_pattern(module.into_iter()))
}
fn desugar_pattern_in_block(&mut self, block: Block) -> Block {
Block::new(self.desugar_pattern(block.into_iter()))
}
fn desugar_pattern<I>(&mut self, chunks: I) -> Vec<Expr>
where
I: IntoIterator<Item = Expr> + ExactSizeIterator,
{
let mut new = Vec::with_capacity(chunks.len());
for chunk in chunks.into_iter() {
match chunk {
Expr::Def(Def {
sig: Signature::Var(v),
body,
}) => match &v.pat {
VarPattern::Tuple(tup) => {
let (buf_name, buf_sig) =
self.gen_buf_name_and_sig(v.ln_begin().unwrap_or(1), v.t_spec);
let block = body
.block
.into_iter()
.map(|ex| self.rec_desugar_lambda_pattern(ex))
.collect();
let block = self.desugar_pattern_in_block(block);
let buf_def = Def::new(buf_sig, DefBody::new(body.op, block, body.id));
new.push(Expr::Def(buf_def));
for (n, elem) in tup.elems.iter().enumerate() {
self.desugar_nested_var_pattern(
&mut new,
elem,
&buf_name,
BufIndex::Tuple(n),
);
}
}
VarPattern::Array(arr) => {
let (buf_name, buf_sig) =
self.gen_buf_name_and_sig(v.ln_begin().unwrap_or(1), v.t_spec);
let block = body
.block
.into_iter()
.map(|ex| self.rec_desugar_lambda_pattern(ex))
.collect();
let block = self.desugar_pattern_in_block(block);
let buf_def = Def::new(buf_sig, DefBody::new(body.op, block, body.id));
new.push(Expr::Def(buf_def));
for (n, elem) in arr.elems.iter().enumerate() {
self.desugar_nested_var_pattern(
&mut new,
elem,
&buf_name,
BufIndex::Array(n),
);
}
}
VarPattern::Record(rec) => {
let (buf_name, buf_sig) =
self.gen_buf_name_and_sig(v.ln_begin().unwrap_or(1), v.t_spec);
let block = body
.block
.into_iter()
.map(|ex| self.rec_desugar_lambda_pattern(ex))
.collect();
let block = self.desugar_pattern_in_block(block);
let buf_def = Def::new(buf_sig, DefBody::new(body.op, block, body.id));
new.push(Expr::Def(buf_def));
for VarRecordAttr { lhs, rhs } in rec.attrs.iter() {
self.desugar_nested_var_pattern(
&mut new,
rhs,
&buf_name,
BufIndex::Record(lhs),
);
}
}
VarPattern::DataPack(pack) => {
let (buf_name, buf_sig) = self.gen_buf_name_and_sig(
v.ln_begin().unwrap_or(1),
Some(pack.class.clone()), );
let block = body
.block
.into_iter()
.map(|ex| self.rec_desugar_lambda_pattern(ex))
.collect();
let block = self.desugar_pattern_in_block(block);
let buf_def = Def::new(buf_sig, DefBody::new(body.op, block, body.id));
new.push(Expr::Def(buf_def));
for VarRecordAttr { lhs, rhs } in pack.args.attrs.iter() {
self.desugar_nested_var_pattern(
&mut new,
rhs,
&buf_name,
BufIndex::Record(lhs),
);
}
}
VarPattern::Ident(_) | VarPattern::Discard(_) => {
let block = body
.block
.into_iter()
.map(|ex| self.rec_desugar_lambda_pattern(ex))
.collect();
let block = self.desugar_pattern_in_block(block);
let body = DefBody::new(body.op, block, body.id);
let def = Def::new(Signature::Var(v), body);
new.push(Expr::Def(def));
}
},
Expr::Def(Def {
sig: Signature::Subr(mut subr),
mut body,
}) => {
let non_defaults = subr.params.non_defaults.iter_mut();
for param in non_defaults {
self.desugar_nd_param(param, &mut body.block);
}
let block = body
.block
.into_iter()
.map(|ex| self.rec_desugar_lambda_pattern(ex))
.collect();
let block = self.desugar_pattern_in_block(block);
let body = DefBody::new(body.op, block, body.id);
let def = Def::new(Signature::Subr(subr), body);
new.push(Expr::Def(def));
}
Expr::Dummy(dummy) => {
let loc = dummy.loc;
let new_dummy = self.desugar_pattern(dummy.into_iter());
new.push(Expr::Dummy(Dummy::new(loc, new_dummy)));
}
other => {
new.push(self.rec_desugar_lambda_pattern(other));
}
}
}
new
}
fn desugar_nested_var_pattern(
&mut self,
new_module: &mut Vec<Expr>,
sig: &VarSignature,
buf_name: &str,
buf_index: BufIndex,
) {
let obj = Expr::local(
buf_name,
sig.ln_begin().unwrap_or(1),
sig.col_begin().unwrap_or(0),
);
let acc = match buf_index {
BufIndex::Tuple(n) => obj.tuple_attr(Literal::nat(n, sig.ln_begin().unwrap_or(1))),
BufIndex::Array(n) => {
let r_brace = Token::new(
TokenKind::RBrace,
"]",
sig.ln_begin().unwrap_or(1),
sig.col_begin().unwrap_or(0),
);
obj.subscr(
Expr::Literal(Literal::nat(n, sig.ln_begin().unwrap_or(1))),
r_brace,
)
}
BufIndex::Record(attr) => {
let attr = Identifier::new(VisModifierSpec::Auto, attr.name.clone());
obj.attr(attr)
}
};
let id = DefId(get_hash(&(&acc, buf_name)));
let block = Block::new(vec![Expr::Accessor(acc)]);
let op = Token::from_str(TokenKind::Equal, "=");
let body = DefBody::new(op, block, id);
match &sig.pat {
VarPattern::Tuple(tup) => {
let (buf_name, buf_sig) =
self.gen_buf_name_and_sig(sig.ln_begin().unwrap_or(1), None);
let buf_def = Def::new(buf_sig, body);
new_module.push(Expr::Def(buf_def));
for (n, elem) in tup.elems.iter().enumerate() {
self.desugar_nested_var_pattern(
new_module,
elem,
&buf_name,
BufIndex::Tuple(n),
);
}
}
VarPattern::Array(arr) => {
let (buf_name, buf_sig) =
self.gen_buf_name_and_sig(sig.ln_begin().unwrap_or(1), None);
let buf_def = Def::new(buf_sig, body);
new_module.push(Expr::Def(buf_def));
for (n, elem) in arr.elems.iter().enumerate() {
self.desugar_nested_var_pattern(
new_module,
elem,
&buf_name,
BufIndex::Array(n),
);
}
}
VarPattern::Record(rec) => {
let (buf_name, buf_sig) =
self.gen_buf_name_and_sig(sig.ln_begin().unwrap_or(1), None);
let buf_def = Def::new(buf_sig, body);
new_module.push(Expr::Def(buf_def));
for VarRecordAttr { lhs, rhs } in rec.attrs.iter() {
self.desugar_nested_var_pattern(
new_module,
rhs,
&buf_name,
BufIndex::Record(lhs),
);
}
}
VarPattern::DataPack(pack) => {
let (buf_name, buf_sig) = self
.gen_buf_name_and_sig(sig.ln_begin().unwrap_or(1), Some(pack.class.clone()));
let buf_def = Def::new(buf_sig, body);
new_module.push(Expr::Def(buf_def));
for VarRecordAttr { lhs, rhs } in pack.args.attrs.iter() {
self.desugar_nested_var_pattern(
new_module,
rhs,
&buf_name,
BufIndex::Record(lhs),
);
}
}
VarPattern::Ident(_) | VarPattern::Discard(_) => {
let def = Def::new(Signature::Var(sig.clone()), body);
new_module.push(Expr::Def(def));
}
}
}
fn desugar_shortened_record(module: Module) -> Module {
Self::desugar_all_chunks(module, Self::rec_desugar_shortened_record)
}
fn rec_desugar_shortened_record(expr: Expr) -> Expr {
match expr {
Expr::Record(Record::Mixed(record)) => {
let rec = Self::desugar_shortened_record_inner(record);
Expr::Record(Record::Normal(rec))
}
Expr::DataPack(pack) => {
if let Record::Mixed(rec) = pack.args {
let class = Self::rec_desugar_shortened_record(*pack.class);
let rec = Self::desugar_shortened_record_inner(rec);
let args = Record::Normal(rec);
Expr::DataPack(DataPack::new(class, pack.connector, args))
} else {
Expr::DataPack(pack)
}
}
expr => Self::perform_desugar(Self::rec_desugar_shortened_record, expr),
}
}
pub(crate) fn desugar_shortened_record_inner(record: MixedRecord) -> NormalRecord {
let attrs = record
.attrs
.into_iter()
.map(|attr_or_ident| match attr_or_ident {
RecordAttrOrIdent::Attr(def) => def,
RecordAttrOrIdent::Ident(ident) => {
let var = VarSignature::new(VarPattern::Ident(ident.clone()), None);
let sig = Signature::Var(var);
let body = DefBody::new(
Token::from_str(TokenKind::Equal, "="),
Block::new(vec![Expr::local(
ident.inspect(),
ident.ln_begin().unwrap_or(1),
ident.col_begin().unwrap_or(0),
)]),
DefId(get_hash(&(&sig, ident.inspect()))),
);
Def::new(sig, body)
}
})
.collect();
let attrs = RecordAttrs::new(attrs);
NormalRecord::new(record.l_brace, record.r_brace, attrs)
}
fn dummy_array_expr(len: Literal) -> Expr {
let l_sqbr = Token {
content: "[".into(),
kind: TokenKind::LSqBr,
..len.token
};
let r_sqbr = Token {
content: "]".into(),
kind: TokenKind::RSqBr,
..len.token
};
let elem = Expr::local("Obj", l_sqbr.lineno, l_sqbr.col_begin);
let array = Array::WithLength(ArrayWithLength::new(
l_sqbr,
r_sqbr,
PosArg::new(elem),
Expr::Literal(len),
));
Expr::Array(array)
}
fn dummy_set_expr(lit: Literal) -> Expr {
let l_brace = Token {
content: "{".into(),
kind: TokenKind::LBrace,
..lit.token
};
let r_brace = Token {
content: "}".into(),
kind: TokenKind::RBrace,
..lit.token
};
let args = Args::single(PosArg::new(Expr::Literal(lit)));
Expr::from(NormalSet::new(l_brace, r_brace, args))
}
fn desugar_nd_param(&mut self, param: &mut NonDefaultParamSignature, body: &mut Block) {
let mut insertion_idx = 0;
let line = param.ln_begin().unwrap_or(1);
match &mut param.pat {
ParamPattern::VarName(_v) => {}
ParamPattern::Lit(l) => {
let lit = l.clone();
param.pat = ParamPattern::Discard(Token::new(
TokenKind::UBar,
"_",
l.ln_begin().unwrap_or(1),
l.col_begin().unwrap_or(0),
));
let l_brace = Token {
content: "{".into(),
kind: TokenKind::LBrace,
..lit.token
};
let r_brace = Token {
content: "}".into(),
kind: TokenKind::RBrace,
..lit.token
};
let t_spec = TypeSpec::enum_t_spec(vec![lit.clone()]);
let args = Args::single(PosArg::new(Expr::Literal(lit)));
let t_spec_as_expr = Expr::from(NormalSet::new(l_brace, r_brace, args));
let t_spec = TypeSpecWithOp::new(COLON, t_spec, t_spec_as_expr);
param.t_spec = Some(t_spec);
}
ParamPattern::Tuple(tup) => {
let (buf_name, buf_param) = self.gen_buf_nd_param(line);
let mut ty_specs = vec![];
let mut ty_exprs = vec![];
for (n, elem) in tup.elems.non_defaults.iter_mut().enumerate() {
insertion_idx = self.desugar_nested_param_pattern(
body,
elem,
&buf_name,
BufIndex::Tuple(n),
insertion_idx,
);
let infer = Token::new(TokenKind::Try, "?", line, 0);
let ty_expr = elem
.t_spec
.as_ref()
.map(|ts| *ts.t_spec_as_expr.clone())
.unwrap_or(Expr::local("Obj", infer.lineno, infer.col_begin));
ty_exprs.push(PosArg::new(ty_expr));
ty_specs.push(
elem.t_spec
.as_ref()
.map(|ts| ts.t_spec.clone())
.unwrap_or(TypeSpec::Infer(infer))
.clone(),
);
}
if param.t_spec.is_none() {
let t_spec =
TypeSpec::Tuple(TupleTypeSpec::new(tup.elems.parens.clone(), ty_specs));
let t_spec_as_expr = Expr::from(NormalTuple::new(Args::pos_only(
ty_exprs,
tup.elems.parens.clone(),
)));
param.t_spec = Some(TypeSpecWithOp::new(COLON, t_spec, t_spec_as_expr));
}
param.pat = buf_param;
}
ParamPattern::Array(arr) => {
let (buf_name, buf_param) = self.gen_buf_nd_param(line);
for (n, elem) in arr.elems.non_defaults.iter_mut().enumerate() {
insertion_idx = self.desugar_nested_param_pattern(
body,
elem,
&buf_name,
BufIndex::Array(n),
insertion_idx,
);
}
if param.t_spec.is_none() {
let len = arr.elems.non_defaults.len();
let len = Literal::new(Token::new(TokenKind::NatLit, len.to_string(), line, 0));
let infer = Token::new(TokenKind::Try, "?", line, 0);
let t_spec =
ArrayTypeSpec::new(TypeSpec::Infer(infer), ConstExpr::Lit(len.clone()));
let t_spec_as_expr = Self::dummy_array_expr(len);
param.t_spec = Some(TypeSpecWithOp::new(
Token::dummy(TokenKind::Colon, ":"),
TypeSpec::Array(t_spec),
t_spec_as_expr,
));
}
param.pat = buf_param;
}
ParamPattern::Record(rec) => {
let (buf_name, buf_param) = self.gen_buf_nd_param(line);
for ParamRecordAttr { lhs, rhs } in rec.elems.iter_mut() {
insertion_idx = self.desugar_nested_param_pattern(
body,
rhs,
&buf_name,
BufIndex::Record(lhs),
insertion_idx,
);
}
if param.t_spec.is_none() {
let mut attrs = RecordAttrs::new(vec![]);
let mut tys = vec![];
for ParamRecordAttr { lhs, rhs } in rec.elems.iter() {
let infer = Token::new(TokenKind::Try, "?", line, 0);
let expr = rhs
.t_spec
.as_ref()
.map(|ts| *ts.t_spec_as_expr.clone())
.unwrap_or(Expr::local("Obj", infer.lineno, infer.col_begin));
let attr =
Def::new(Signature::new_var(lhs.clone()), DefBody::new_single(expr));
attrs.push(attr);
tys.push((
lhs.clone(),
rhs.t_spec
.as_ref()
.map(|ts| ts.t_spec.clone())
.unwrap_or(TypeSpec::Infer(infer))
.clone(),
));
}
let t_spec = TypeSpec::Record(tys);
let t_spec_as_expr = Expr::from(NormalRecord::new(
rec.l_brace.clone(),
rec.r_brace.clone(),
attrs,
));
param.t_spec = Some(TypeSpecWithOp::new(COLON, t_spec, t_spec_as_expr));
}
param.pat = buf_param;
}
_ => {}
}
}
fn desugar_nested_param_pattern(
&mut self,
new_body: &mut Block,
sig: &mut NonDefaultParamSignature,
buf_name: &str,
buf_index: BufIndex,
mut insertion_idx: usize,
) -> usize {
let obj = Expr::local(
buf_name,
sig.ln_begin().unwrap_or(1),
sig.col_begin().unwrap_or(0),
);
let acc = match buf_index {
BufIndex::Tuple(n) => obj.tuple_attr(Literal::nat(n, sig.ln_begin().unwrap_or(1))),
BufIndex::Array(n) => {
let r_brace = Token::new(
TokenKind::RBrace,
"]",
sig.ln_begin().unwrap_or(1),
sig.col_begin().unwrap_or(0),
);
obj.subscr(
Expr::Literal(Literal::nat(n, sig.ln_begin().unwrap_or(1))),
r_brace,
)
}
BufIndex::Record(attr) => {
let attr = Identifier::new(VisModifierSpec::Auto, attr.name.clone());
obj.attr(attr)
}
};
let id = DefId(get_hash(&(&acc, buf_name)));
let block = Block::new(vec![Expr::Accessor(acc)]);
let op = Token::from_str(TokenKind::Equal, "=");
let body = DefBody::new(op, block, id);
let line = sig.ln_begin().unwrap_or(1);
match &mut sig.pat {
ParamPattern::Tuple(tup) => {
let (buf_name, buf_sig) = self.gen_buf_nd_param(line);
let ident = Identifier::private(Str::from(&buf_name));
new_body.insert(
insertion_idx,
Expr::Def(Def::new(
Signature::Var(VarSignature::new(
VarPattern::Ident(ident),
sig.t_spec.as_ref().map(|ts| ts.t_spec.clone()),
)),
body,
)),
);
insertion_idx += 1;
let mut ty_exprs = vec![];
let mut tys = vec![];
for (n, elem) in tup.elems.non_defaults.iter_mut().enumerate() {
insertion_idx = self.desugar_nested_param_pattern(
new_body,
elem,
&buf_name,
BufIndex::Tuple(n),
insertion_idx,
);
let infer = Token::new(TokenKind::Try, "?", line, 0);
let ty_expr = elem
.t_spec
.as_ref()
.map(|ts| *ts.t_spec_as_expr.clone())
.unwrap_or(Expr::local("Obj", infer.lineno, infer.col_begin));
ty_exprs.push(PosArg::new(ty_expr));
tys.push(
elem.t_spec
.as_ref()
.map(|ts| ts.t_spec.clone())
.unwrap_or(TypeSpec::Infer(infer))
.clone(),
);
}
if sig.t_spec.is_none() {
let t_spec = TypeSpec::Tuple(TupleTypeSpec::new(tup.elems.parens.clone(), tys));
let t_spec_as_expr = Expr::from(NormalTuple::new(Args::pos_only(
ty_exprs,
tup.elems.parens.clone(),
)));
sig.t_spec = Some(TypeSpecWithOp::new(COLON, t_spec, t_spec_as_expr));
}
sig.pat = buf_sig;
insertion_idx
}
ParamPattern::Array(arr) => {
let (buf_name, buf_sig) = self.gen_buf_nd_param(line);
new_body.insert(
insertion_idx,
Expr::Def(Def::new(
Signature::Var(VarSignature::new(
VarPattern::Ident(Identifier::private(Str::from(&buf_name))),
sig.t_spec.as_ref().map(|ts| ts.t_spec.clone()),
)),
body,
)),
);
insertion_idx += 1;
for (n, elem) in arr.elems.non_defaults.iter_mut().enumerate() {
insertion_idx = self.desugar_nested_param_pattern(
new_body,
elem,
&buf_name,
BufIndex::Array(n),
insertion_idx,
);
}
if sig.t_spec.is_none() {
let len = arr.elems.non_defaults.len();
let len = Literal::new(Token::new(TokenKind::NatLit, len.to_string(), line, 0));
let infer = Token::new(TokenKind::Try, "?", line, 0);
let t_spec =
ArrayTypeSpec::new(TypeSpec::Infer(infer), ConstExpr::Lit(len.clone()));
let t_spec_as_expr = Self::dummy_array_expr(len);
sig.t_spec = Some(TypeSpecWithOp::new(
COLON,
TypeSpec::Array(t_spec),
t_spec_as_expr,
));
}
sig.pat = buf_sig;
insertion_idx
}
ParamPattern::Record(rec) => {
let (buf_name, buf_sig) = self.gen_buf_nd_param(line);
new_body.insert(
insertion_idx,
Expr::Def(Def::new(
Signature::Var(VarSignature::new(
VarPattern::Ident(Identifier::private(Str::from(&buf_name))),
sig.t_spec.as_ref().map(|ts| ts.t_spec.clone()),
)),
body,
)),
);
insertion_idx += 1;
let mut attrs = RecordAttrs::new(vec![]);
let mut tys = vec![];
for ParamRecordAttr { lhs, rhs } in rec.elems.iter_mut() {
insertion_idx = self.desugar_nested_param_pattern(
new_body,
rhs,
&buf_name,
BufIndex::Record(lhs),
insertion_idx,
);
let infer = Token::new(TokenKind::Try, "?", line, 0);
let expr = rhs
.t_spec
.as_ref()
.map(|ts| *ts.t_spec_as_expr.clone())
.unwrap_or(Expr::local("Obj", infer.lineno, infer.col_begin));
let attr = Def::new(Signature::new_var(lhs.clone()), DefBody::new_single(expr));
attrs.push(attr);
tys.push((
lhs.clone(),
rhs.t_spec
.as_ref()
.map(|ts| ts.t_spec.clone())
.unwrap_or(TypeSpec::Infer(infer))
.clone(),
));
}
if sig.t_spec.is_none() {
let t_spec = TypeSpec::Record(tys);
let t_spec_as_expr = Expr::from(NormalRecord::new(
rec.l_brace.clone(),
rec.r_brace.clone(),
attrs,
));
sig.t_spec = Some(TypeSpecWithOp::new(COLON, t_spec, t_spec_as_expr));
}
sig.pat = buf_sig;
insertion_idx
}
ParamPattern::VarName(name) => {
let ident = Identifier::new(VisModifierSpec::Private, name.clone());
let v = VarSignature::new(
VarPattern::Ident(ident),
sig.t_spec.as_ref().map(|ts| ts.t_spec.clone()),
);
let def = Def::new(Signature::Var(v), body);
new_body.insert(insertion_idx, Expr::Def(def));
insertion_idx += 1;
insertion_idx
}
ParamPattern::Lit(l) => {
let lit = l.clone();
sig.pat = ParamPattern::Discard(Token::new(
TokenKind::UBar,
"_",
l.ln_begin().unwrap_or(1),
l.col_begin().unwrap_or(1),
));
let t_spec = TypeSpec::enum_t_spec(vec![lit.clone()]);
let t_spec_as_expr = Self::dummy_set_expr(lit);
sig.t_spec = Some(TypeSpecWithOp::new(COLON, t_spec, t_spec_as_expr));
insertion_idx
}
_ => insertion_idx,
}
}
fn _desugar_self(module: Module) -> Module {
Self::desugar_all_chunks(module, Self::_desugar_self_inner)
}
fn _desugar_self_inner(_expr: Expr) -> Expr {
todo!()
}
fn _desugar_refinement_pattern(_mod: Module) -> Module {
todo!()
}
fn desugar_acc(module: Module) -> Module {
Self::desugar_all_chunks(module, Self::rec_desugar_acc)
}
fn rec_desugar_acc(expr: Expr) -> Expr {
match expr {
Expr::Accessor(acc) => Self::desugar_acc_inner(acc),
expr => Self::perform_desugar(Self::rec_desugar_acc, expr),
}
}
fn desugar_acc_inner(acc: Accessor) -> Expr {
match acc {
Accessor::Subscr(subscr) => {
let args = Args::single(PosArg::new(Self::rec_desugar_acc(*subscr.index)));
let line = subscr.obj.ln_begin().unwrap_or(1);
let call = Call::new(
Self::rec_desugar_acc(*subscr.obj),
Some(Identifier::public_with_line(
DOT,
Str::ever("__getitem__"),
line,
)),
args,
);
Expr::Call(call)
}
Accessor::TupleAttr(tattr) => {
let args = Args::single(PosArg::new(Expr::Literal(tattr.index)));
let line = tattr.obj.ln_begin().unwrap_or(1);
let call = Call::new(
Self::rec_desugar_acc(*tattr.obj),
Some(Identifier::public_with_line(
DOT,
Str::ever("__Tuple_getitem__"),
line,
)),
args,
);
Expr::Call(call)
}
Accessor::TypeApp(mut tapp) => {
tapp.obj = Box::new(Self::rec_desugar_acc(*tapp.obj));
Expr::Accessor(Accessor::TypeApp(tapp))
}
Accessor::Attr(mut attr) => {
attr.obj = Box::new(Self::rec_desugar_acc(*attr.obj));
Expr::Accessor(Accessor::Attr(attr))
}
other => Expr::Accessor(other),
}
}
}
impl Default for Desugarer {
fn default() -> Self {
Self::new()
}
}