1 // Copyright 2012 The Rust Project Developers. See the COPYRIGHT
2 // file at the top-level directory of this distribution and at
3 // http://rust-lang.org/COPYRIGHT.
5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
8 // option. This file may not be copied, modified, or distributed
9 // except according to those terms.
13 More runtime type reflection
17 #[allow(missing_doc)];
21 use container::Container;
25 use option::{Some, None};
28 use reflect::{MovePtr, align};
32 use unstable::intrinsics::{Disr, Opaque, TyDesc, TyVisitor, get_tydesc, visit_tydesc};
38 fn write_repr(&self, writer: &mut io::Writer);
42 fn write_repr(&self, writer: &mut io::Writer) {
43 writer.write("()".as_bytes());
48 fn write_repr(&self, writer: &mut io::Writer) {
49 let s = if *self { "true" } else { "false" };
50 writer.write(s.as_bytes())
55 fn write_repr(&self, writer: &mut io::Writer) {
56 ::int::to_str_bytes(*self, 10u, |bits| {
62 macro_rules! int_repr(($ty:ident, $suffix:expr) => (impl Repr for $ty {
63 fn write_repr(&self, writer: &mut io::Writer) {
64 ::$ty::to_str_bytes(*self, 10u, |bits| {
66 writer.write(bytes!($suffix));
81 macro_rules! num_repr(($ty:ident, $suffix:expr) => (impl Repr for $ty {
82 fn write_repr(&self, writer: &mut io::Writer) {
83 let s = self.to_str();
84 writer.write(s.as_bytes());
85 writer.write(bytes!($suffix));
92 // New implementation using reflect::MovePtr
100 pub struct ReprVisitor<'a> {
102 priv ptr_stk: ~[*c_void],
103 priv var_stk: ~[VariantState],
104 priv writer: &'a mut io::Writer
107 pub fn ReprVisitor<'a>(ptr: *c_void,
108 writer: &'a mut io::Writer) -> ReprVisitor<'a> {
117 impl<'a> MovePtr for ReprVisitor<'a> {
119 fn move_ptr(&mut self, adjustment: |*c_void| -> *c_void) {
120 self.ptr = adjustment(self.ptr);
122 fn push_ptr(&mut self) {
123 self.ptr_stk.push(self.ptr);
125 fn pop_ptr(&mut self) {
126 self.ptr = self.ptr_stk.pop();
130 impl<'a> ReprVisitor<'a> {
131 // Various helpers for the TyVisitor impl
134 pub fn get<T>(&mut self, f: |&mut ReprVisitor, &T|) -> bool {
136 f(self, transmute::<*c_void,&T>(self.ptr));
142 pub fn visit_inner(&mut self, inner: *TyDesc) -> bool {
143 self.visit_ptr_inner(self.ptr, inner)
147 pub fn visit_ptr_inner(&mut self, ptr: *c_void, inner: *TyDesc) -> bool {
149 // This should call the constructor up above, but due to limiting
150 // issues we have to recreate it here.
151 let u = ReprVisitor {
155 writer: ::cast::transmute_copy(&self.writer),
157 let mut v = reflect::MovePtrAdaptor(u);
158 // Obviously this should not be a thing, but blame #8401 for now
159 visit_tydesc(inner, &mut v as &mut TyVisitor);
165 pub fn write<T:Repr>(&mut self) -> bool {
166 self.get(|this, v:&T| {
167 v.write_repr(unsafe { ::cast::transmute_copy(&this.writer) });
171 pub fn write_escaped_slice(&mut self, slice: &str) {
172 self.writer.write(['"' as u8]);
173 for ch in slice.chars() {
174 self.write_escaped_char(ch, true);
176 self.writer.write(['"' as u8]);
179 pub fn write_mut_qualifier(&mut self, mtbl: uint) {
181 self.writer.write("mut ".as_bytes());
182 } else if mtbl == 1 {
183 // skip, this is ast::m_imm
185 fail!("invalid mutability value");
189 pub fn write_vec_range(&mut self, ptr: *(), len: uint, inner: *TyDesc) -> bool {
190 let mut p = ptr as *u8;
191 let (sz, al) = unsafe { ((*inner).size, (*inner).align) };
192 self.writer.write(['[' as u8]);
193 let mut first = true;
195 // unit structs have 0 size, and don't loop forever.
196 let dec = if sz == 0 {1} else {sz};
201 self.writer.write(", ".as_bytes());
203 self.visit_ptr_inner(p as *c_void, inner);
204 p = align(unsafe { ptr::offset(p, sz as int) as uint }, al) as *u8;
207 self.writer.write([']' as u8]);
211 pub fn write_unboxed_vec_repr(&mut self, _: uint, v: &raw::Vec<()>, inner: *TyDesc) -> bool {
212 self.write_vec_range(ptr::to_unsafe_ptr(&v.data), v.fill, inner)
215 fn write_escaped_char(&mut self, ch: char, is_str: bool) {
217 '\t' => self.writer.write("\\t".as_bytes()),
218 '\r' => self.writer.write("\\r".as_bytes()),
219 '\n' => self.writer.write("\\n".as_bytes()),
220 '\\' => self.writer.write("\\\\".as_bytes()),
223 self.writer.write("'".as_bytes())
225 self.writer.write("\\'".as_bytes())
230 self.writer.write("\\\"".as_bytes())
232 self.writer.write("\"".as_bytes())
235 '\x20'..'\x7e' => self.writer.write([ch as u8]),
237 char::escape_unicode(ch, |c| {
238 self.writer.write([c as u8]);
245 impl<'a> TyVisitor for ReprVisitor<'a> {
246 fn visit_bot(&mut self) -> bool {
247 self.writer.write("!".as_bytes());
250 fn visit_nil(&mut self) -> bool { self.write::<()>() }
251 fn visit_bool(&mut self) -> bool { self.write::<bool>() }
252 fn visit_int(&mut self) -> bool { self.write::<int>() }
253 fn visit_i8(&mut self) -> bool { self.write::<i8>() }
254 fn visit_i16(&mut self) -> bool { self.write::<i16>() }
255 fn visit_i32(&mut self) -> bool { self.write::<i32>() }
256 fn visit_i64(&mut self) -> bool { self.write::<i64>() }
258 fn visit_uint(&mut self) -> bool { self.write::<uint>() }
259 fn visit_u8(&mut self) -> bool { self.write::<u8>() }
260 fn visit_u16(&mut self) -> bool { self.write::<u16>() }
261 fn visit_u32(&mut self) -> bool { self.write::<u32>() }
262 fn visit_u64(&mut self) -> bool { self.write::<u64>() }
264 fn visit_f32(&mut self) -> bool { self.write::<f32>() }
265 fn visit_f64(&mut self) -> bool { self.write::<f64>() }
267 fn visit_char(&mut self) -> bool {
268 self.get::<char>(|this, &ch| {
269 this.writer.write(['\'' as u8]);
270 this.write_escaped_char(ch, false);
271 this.writer.write(['\'' as u8]);
275 fn visit_estr_box(&mut self) -> bool {
276 self.get::<@str>(|this, s| {
277 this.writer.write(['@' as u8]);
278 this.write_escaped_slice(*s);
282 fn visit_estr_uniq(&mut self) -> bool {
283 self.get::<~str>(|this, s| {
284 this.writer.write(['~' as u8]);
285 this.write_escaped_slice(*s);
289 fn visit_estr_slice(&mut self) -> bool {
290 self.get::<&str>(|this, s| this.write_escaped_slice(*s))
293 // Type no longer exists, vestigial function.
294 fn visit_estr_fixed(&mut self, _n: uint, _sz: uint,
295 _align: uint) -> bool { fail!(); }
297 fn visit_box(&mut self, mtbl: uint, inner: *TyDesc) -> bool {
298 self.writer.write(['@' as u8]);
299 self.write_mut_qualifier(mtbl);
300 self.get::<&raw::Box<()>>(|this, b| {
301 let p = ptr::to_unsafe_ptr(&b.data) as *c_void;
302 this.visit_ptr_inner(p, inner);
306 fn visit_uniq(&mut self, _mtbl: uint, inner: *TyDesc) -> bool {
307 self.writer.write(['~' as u8]);
308 self.get::<*c_void>(|this, b| {
309 this.visit_ptr_inner(*b, inner);
313 fn visit_ptr(&mut self, mtbl: uint, _inner: *TyDesc) -> bool {
314 self.get::<*c_void>(|this, p| {
315 write!(this.writer, "({} as *", *p);
316 this.write_mut_qualifier(mtbl);
317 this.writer.write("())".as_bytes());
321 fn visit_rptr(&mut self, mtbl: uint, inner: *TyDesc) -> bool {
322 self.writer.write(['&' as u8]);
323 self.write_mut_qualifier(mtbl);
324 self.get::<*c_void>(|this, p| {
325 this.visit_ptr_inner(*p, inner);
329 // Type no longer exists, vestigial function.
330 fn visit_vec(&mut self, _mtbl: uint, _inner: *TyDesc) -> bool { fail!(); }
332 fn visit_unboxed_vec(&mut self, mtbl: uint, inner: *TyDesc) -> bool {
333 self.get::<raw::Vec<()>>(|this, b| {
334 this.write_unboxed_vec_repr(mtbl, b, inner);
338 fn visit_evec_box(&mut self, mtbl: uint, inner: *TyDesc) -> bool {
339 self.get::<&raw::Box<raw::Vec<()>>>(|this, b| {
340 this.writer.write(['@' as u8]);
341 this.write_mut_qualifier(mtbl);
342 this.write_unboxed_vec_repr(mtbl, &b.data, inner);
346 fn visit_evec_uniq(&mut self, mtbl: uint, inner: *TyDesc) -> bool {
347 self.get::<&raw::Vec<()>>(|this, b| {
348 this.writer.write(['~' as u8]);
349 this.write_unboxed_vec_repr(mtbl, *b, inner);
353 fn visit_evec_slice(&mut self, mtbl: uint, inner: *TyDesc) -> bool {
354 self.get::<raw::Slice<()>>(|this, s| {
355 this.writer.write(['&' as u8]);
356 this.write_mut_qualifier(mtbl);
358 if (*inner).size == 0 { 1 } else { (*inner).size }
360 this.write_vec_range(s.data, s.len * size, inner);
364 fn visit_evec_fixed(&mut self, n: uint, sz: uint, _align: uint,
365 _: uint, inner: *TyDesc) -> bool {
366 let assumed_size = if sz == 0 { n } else { sz };
367 self.get::<()>(|this, b| {
368 this.write_vec_range(ptr::to_unsafe_ptr(b), assumed_size, inner);
372 fn visit_enter_rec(&mut self, _n_fields: uint,
373 _sz: uint, _align: uint) -> bool {
374 self.writer.write(['{' as u8]);
378 fn visit_rec_field(&mut self, i: uint, name: &str,
379 mtbl: uint, inner: *TyDesc) -> bool {
381 self.writer.write(", ".as_bytes());
383 self.write_mut_qualifier(mtbl);
384 self.writer.write(name.as_bytes());
385 self.writer.write(": ".as_bytes());
386 self.visit_inner(inner);
390 fn visit_leave_rec(&mut self, _n_fields: uint,
391 _sz: uint, _align: uint) -> bool {
392 self.writer.write(['}' as u8]);
396 fn visit_enter_class(&mut self, name: &str, named_fields: bool, n_fields: uint,
397 _sz: uint, _align: uint) -> bool {
398 self.writer.write(name.as_bytes());
401 self.writer.write(['{' as u8]);
403 self.writer.write(['(' as u8]);
409 fn visit_class_field(&mut self, i: uint, name: &str, named: bool,
410 _mtbl: uint, inner: *TyDesc) -> bool {
412 self.writer.write(", ".as_bytes());
415 self.writer.write(name.as_bytes());
416 self.writer.write(": ".as_bytes());
418 self.visit_inner(inner);
422 fn visit_leave_class(&mut self, _name: &str, named_fields: bool, n_fields: uint,
423 _sz: uint, _align: uint) -> bool {
426 self.writer.write(['}' as u8]);
428 self.writer.write([')' as u8]);
434 fn visit_enter_tup(&mut self, _n_fields: uint,
435 _sz: uint, _align: uint) -> bool {
436 self.writer.write(['(' as u8]);
440 fn visit_tup_field(&mut self, i: uint, inner: *TyDesc) -> bool {
442 self.writer.write(", ".as_bytes());
444 self.visit_inner(inner);
448 fn visit_leave_tup(&mut self, _n_fields: uint,
449 _sz: uint, _align: uint) -> bool {
451 self.writer.write([',' as u8]);
453 self.writer.write([')' as u8]);
457 fn visit_enter_enum(&mut self,
459 get_disr: extern unsafe fn(ptr: *Opaque) -> Disr,
461 _align: uint) -> bool {
463 get_disr(transmute(self.ptr))
465 self.var_stk.push(SearchingFor(disr));
469 fn visit_enter_enum_variant(&mut self, _variant: uint,
472 name: &str) -> bool {
473 let mut write = false;
474 match self.var_stk.pop() {
475 SearchingFor(sought) => {
476 if disr_val == sought {
477 self.var_stk.push(Matched);
480 self.var_stk.push(SearchingFor(sought));
483 Matched | AlreadyFound => {
484 self.var_stk.push(AlreadyFound);
489 self.writer.write(name.as_bytes());
491 self.writer.write(['(' as u8]);
497 fn visit_enum_variant_field(&mut self,
502 match self.var_stk[self.var_stk.len() - 1] {
505 self.writer.write(", ".as_bytes());
507 if ! self.visit_inner(inner) {
516 fn visit_leave_enum_variant(&mut self, _variant: uint,
519 _name: &str) -> bool {
520 match self.var_stk[self.var_stk.len() - 1] {
523 self.writer.write([')' as u8]);
531 fn visit_leave_enum(&mut self,
533 _get_disr: extern unsafe fn(ptr: *Opaque) -> Disr,
537 match self.var_stk.pop() {
538 SearchingFor(..) => fail!("enum value matched no variant"),
543 fn visit_enter_fn(&mut self, _purity: uint, _proto: uint,
544 _n_inputs: uint, _retstyle: uint) -> bool {
545 self.writer.write("fn(".as_bytes());
549 fn visit_fn_input(&mut self, i: uint, _mode: uint, inner: *TyDesc) -> bool {
551 self.writer.write(", ".as_bytes());
553 let name = unsafe { (*inner).name };
554 self.writer.write(name.as_bytes());
558 fn visit_fn_output(&mut self, _retstyle: uint, variadic: bool, inner: *TyDesc) -> bool {
560 self.writer.write(", ...".as_bytes());
562 self.writer.write(")".as_bytes());
563 let name = unsafe { (*inner).name };
565 self.writer.write(" -> ".as_bytes());
566 self.writer.write(name.as_bytes());
571 fn visit_leave_fn(&mut self, _purity: uint, _proto: uint,
572 _n_inputs: uint, _retstyle: uint) -> bool { true }
575 fn visit_trait(&mut self, name: &str) -> bool {
576 self.writer.write(name.as_bytes());
580 fn visit_param(&mut self, _i: uint) -> bool { true }
581 fn visit_self(&mut self) -> bool { true }
582 fn visit_type(&mut self) -> bool { true }
584 fn visit_opaque_box(&mut self) -> bool {
585 self.writer.write(['@' as u8]);
586 self.get::<&raw::Box<()>>(|this, b| {
587 let p = ptr::to_unsafe_ptr(&b.data) as *c_void;
588 this.visit_ptr_inner(p, b.type_desc);
592 fn visit_closure_ptr(&mut self, _ck: uint) -> bool { true }
595 pub fn write_repr<T>(writer: &mut io::Writer, object: &T) {
597 let ptr = ptr::to_unsafe_ptr(object) as *c_void;
598 let tydesc = get_tydesc::<T>();
599 let u = ReprVisitor(ptr, writer);
600 let mut v = reflect::MovePtrAdaptor(u);
601 visit_tydesc(tydesc, &mut v as &mut TyVisitor);
605 pub fn repr_to_str<T>(t: &T) -> ~str {
609 let mut result = io::MemWriter::new();
610 write_repr(&mut result as &mut io::Writer, t);
611 str::from_utf8_owned(result.unwrap())
615 struct P {a: int, b: f64}
622 use io::stdio::println;
624 use char::is_alphabetic;
626 fn exact_test<T>(t: &T, e:&str) {
627 let mut m = io::MemWriter::new();
628 write_repr(&mut m as &mut io::Writer, t);
629 let s = str::from_utf8_owned(m.unwrap());
630 assert_eq!(s.as_slice(), e);
633 exact_test(&10, "10");
634 exact_test(&true, "true");
635 exact_test(&false, "false");
636 exact_test(&1.234, "1.234f64");
637 exact_test(&(&"hello"), "\"hello\"");
638 exact_test(&(@"hello"), "@\"hello\"");
639 exact_test(&(~"he\u10f3llo"), "~\"he\\u10f3llo\"");
641 exact_test(&(@10), "@10");
642 exact_test(&(~10), "~10");
643 exact_test(&(&10), "&10");
645 exact_test(&(&mut x), "&mut 10");
647 exact_test(&(0 as *()), "(0x0 as *())");
648 exact_test(&(0 as *mut ()), "(0x0 as *mut ())");
650 exact_test(&(1,), "(1,)");
651 exact_test(&(@[1,2,3,4,5,6,7,8]),
652 "@[1, 2, 3, 4, 5, 6, 7, 8]");
653 exact_test(&(@[1u8,2u8,3u8,4u8]),
654 "@[1u8, 2u8, 3u8, 4u8]");
655 exact_test(&(@["hi", "there"]),
656 "@[\"hi\", \"there\"]");
657 exact_test(&(~["hi", "there"]),
658 "~[\"hi\", \"there\"]");
659 exact_test(&(&["hi", "there"]),
660 "&[\"hi\", \"there\"]");
661 exact_test(&(P{a:10, b:1.234}),
662 "repr::P{a: 10, b: 1.234f64}");
663 exact_test(&(@P{a:10, b:1.234}),
664 "@repr::P{a: 10, b: 1.234f64}");
665 exact_test(&(~P{a:10, b:1.234}),
666 "~repr::P{a: 10, b: 1.234f64}");
667 exact_test(&(10u8, ~"hello"),
668 "(10u8, ~\"hello\")");
669 exact_test(&(10u16, ~"hello"),
670 "(10u16, ~\"hello\")");
671 exact_test(&(10u32, ~"hello"),
672 "(10u32, ~\"hello\")");
673 exact_test(&(10u64, ~"hello"),
674 "(10u64, ~\"hello\")");
676 exact_test(&(&[1, 2]), "&[1, 2]");
677 exact_test(&(&mut [1, 2]), "&mut [1, 2]");
679 exact_test(&'\'', "'\\''");
680 exact_test(&'"', "'\"'");
681 exact_test(&("'"), "\"'\"");
682 exact_test(&("\""), "\"\\\"\"");
684 exact_test(&println, "fn(&str)");
685 exact_test(&swap::<int>, "fn(&mut int, &mut int)");
686 exact_test(&is_alphabetic, "fn(char) -> bool");
687 exact_test(&(~5 as ~ToStr), "~to_str::ToStr:Send");
690 exact_test(&(~[Foo, Foo]), "~[repr::test_repr::Foo, repr::test_repr::Foo]");
692 struct Bar(int, int);
693 exact_test(&(Bar(2, 2)), "repr::test_repr::Bar(2, 2)");