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use crate::{
printer::{Printer, LINE_WIDTH},
Printable,
};
use pomelo_parse::ast;
pub fn print_dec(dec: &ast::Dec) -> String {
let mut printer = Printer::new(LINE_WIDTH);
printer.dec(dec);
printer.output()
}
impl Printable for ast::Dec {
fn print(&self, printer: &mut Printer) -> Option<()> {
printer.dec(self)
}
}
impl Printer {
pub fn dec(&mut self, dec: &ast::Dec) -> Option<()> {
match dec {
ast::Dec::Seq(d) => self.seq_dec(d),
ast::Dec::Val(d) => self.val(d),
ast::Dec::Fun(d) => self.fun(d),
ast::Dec::Type(d) => self.tydec(d),
ast::Dec::Datatype(d) => self.datatype(d),
ast::Dec::DatatypeRep(d) => self.datarep(d),
ast::Dec::Abstype(d) => self.abstype(d),
ast::Dec::Exception(d) => self.exception(d),
ast::Dec::Local(d) => self.local(d),
ast::Dec::Open(d) => self.open(d),
ast::Dec::Infix(d) => self.infix(d),
ast::Dec::Infixr(d) => self.infixr(d),
ast::Dec::Nonfix(d) => self.nonfix(d),
}
}
fn seq_dec(&mut self, d: &ast::SeqDec) -> Option<()> {
self.igroup(0);
for (i, d) in d.declarations().enumerate() {
if i != 0 {
self.linebreak();
}
self.dec(&d)?;
}
self.endgroup();
Some(())
}
fn val(&mut self, d: &ast::ValDec) -> Option<()> {
let tyvars = d.tyvarseq();
let mut bindings = d.bindings().enumerate();
let n_bindings = d.bindings().count();
self.igroup(0);
self.igroup(crate::INDENT);
self.text("val");
self.space();
for t in tyvars {
self.text(t.to_string());
self.space();
}
let (_, b) = bindings.next()?;
self.pat(&b.pat()?)?;
self.space();
self.text("=");
self.space();
self.expr(&b.expr()?)?;
self.endgroup();
if n_bindings > 1 {
self.space();
self.igroup(0);
for (i, b) in bindings {
self.igroup(crate::INDENT);
self.text("and");
self.space();
self.pat(&b.pat()?)?;
self.space();
self.text("=");
self.space();
self.expr(&b.expr()?)?;
self.endgroup();
if i < n_bindings - 1 {
self.linebreak();
}
}
self.endgroup();
}
self.endgroup();
Some(())
}
fn fun(&mut self, _d: &ast::FunDec) -> Option<()> {
todo!()
}
fn tydec(&mut self, _d: &ast::TypeDec) -> Option<()> {
todo!()
}
fn datatype(&mut self, _d: &ast::DatatypeDec) -> Option<()> {
todo!()
}
fn datarep(&mut self, _d: &ast::DatatypeRepDec) -> Option<()> {
todo!()
}
fn abstype(&mut self, _d: &ast::AbstypeDec) -> Option<()> {
todo!()
}
fn exception(&mut self, _d: &ast::ExceptionDec) -> Option<()> {
todo!()
}
fn local(&mut self, _d: &ast::LocalDec) -> Option<()> {
todo!()
}
fn open(&mut self, _d: &ast::OpenDec) -> Option<()> {
todo!()
}
fn infix(&mut self, _d: &ast::InfixDec) -> Option<()> {
todo!()
}
fn infixr(&mut self, _d: &ast::InfixrDec) -> Option<()> {
todo!()
}
fn nonfix(&mut self, _d: &ast::NonfixDec) -> Option<()> {
todo!()
}
}
#[cfg(test)]
mod tests {
use crate::tests::check_dec;
use expect_test::expect;
#[test]
fn valdec_let_expr() {
check_dec(
"val x = let val y = 1 in y end and z = let val a = b in c end and d = 1",
80,
expect![[r#"
val x =
let
val y = 1
in
y
end
and z =
let
val a = b
in
c
end
and d = 1"#]],
);
}
}