[rustc.git] / src / libsyntax_ext / deriving / cmp / partial_ord.rs

// Copyright 2013 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.

pub use self::OrderingOp::*;

use deriving::{path_local, pathvec_std, path_std};
use deriving::generic::*;
use deriving::generic::ty::*;

use syntax::ast::{self, BinOpKind, Expr, MetaItem};
use syntax::ext::base::{Annotatable, ExtCtxt};
use syntax::ext::build::AstBuilder;
use syntax::ptr::P;
use syntax::symbol::Symbol;
use syntax_pos::Span;

pub fn expand_deriving_partial_ord(cx: &mut ExtCtxt,
                                   span: Span,
                                   mitem: &MetaItem,
                                   item: &Annotatable,
                                   push: &mut FnMut(Annotatable)) {
    macro_rules! md {
        ($name:expr, $op:expr, $equal:expr) => { {
            let inline = cx.meta_word(span, Symbol::intern("inline"));
            let attrs = vec![cx.attribute(span, inline)];
            MethodDef {
                name: $name,
                generics: LifetimeBounds::empty(),
                explicit_self: borrowed_explicit_self(),
                args: vec![(borrowed_self(), "other")],
                ret_ty: Literal(path_local!(bool)),
                attributes: attrs,
                is_unsafe: false,
                unify_fieldless_variants: true,
                combine_substructure: combine_substructure(Box::new(|cx, span, substr| {
                    cs_op($op, $equal, cx, span, substr)
                }))
            }
        } }
    }

    let ordering_ty = Literal(path_std!(cx, cmp::Ordering));
    let ret_ty = Literal(Path::new_(pathvec_std!(cx, option::Option),
                                    None,
                                    vec![Box::new(ordering_ty)],
                                    PathKind::Std));

    let inline = cx.meta_word(span, Symbol::intern("inline"));
    let attrs = vec![cx.attribute(span, inline)];

    let partial_cmp_def = MethodDef {
        name: "partial_cmp",
        generics: LifetimeBounds::empty(),
        explicit_self: borrowed_explicit_self(),
        args: vec![(borrowed_self(), "other")],
        ret_ty,
        attributes: attrs,
        is_unsafe: false,
        unify_fieldless_variants: true,
        combine_substructure: combine_substructure(Box::new(|cx, span, substr| {
            cs_partial_cmp(cx, span, substr)
        })),
    };

    // avoid defining extra methods if we can
    // c-like enums, enums without any fields and structs without fields
    // can safely define only `partial_cmp`.
    let methods = if is_type_without_fields(item) {
        vec![partial_cmp_def]
    } else {
        vec![partial_cmp_def,
             md!("lt", true, false),
             md!("le", true, true),
             md!("gt", false, false),
             md!("ge", false, true)]
    };

    let trait_def = TraitDef {
        span,
        attributes: vec![],
        path: path_std!(cx, cmp::PartialOrd),
        additional_bounds: vec![],
        generics: LifetimeBounds::empty(),
        is_unsafe: false,
        supports_unions: false,
        methods,
        associated_types: Vec::new(),
    };
    trait_def.expand(cx, mitem, item, push)
}

#[derive(Copy, Clone)]
pub enum OrderingOp {
    PartialCmpOp,
    LtOp,
    LeOp,
    GtOp,
    GeOp,
}

pub fn some_ordering_collapsed(cx: &mut ExtCtxt,
                               span: Span,
                               op: OrderingOp,
                               self_arg_tags: &[ast::Ident])
                               -> P<ast::Expr> {
    let lft = cx.expr_ident(span, self_arg_tags[0]);
    let rgt = cx.expr_addr_of(span, cx.expr_ident(span, self_arg_tags[1]));
    let op_str = match op {
        PartialCmpOp => "partial_cmp",
        LtOp => "lt",
        LeOp => "le",
        GtOp => "gt",
        GeOp => "ge",
    };
    cx.expr_method_call(span, lft, cx.ident_of(op_str), vec![rgt])
}

pub fn cs_partial_cmp(cx: &mut ExtCtxt, span: Span, substr: &Substructure) -> P<Expr> {
    let test_id = cx.ident_of("cmp").gensym();
    let ordering = cx.path_global(span, cx.std_path(&["cmp", "Ordering", "Equal"]));
    let ordering_expr = cx.expr_path(ordering.clone());
    let equals_expr = cx.expr_some(span, ordering_expr);

    let partial_cmp_path = cx.std_path(&["cmp", "PartialOrd", "partial_cmp"]);

    // Builds:
    //
    // match ::std::cmp::PartialOrd::partial_cmp(&self_field1, &other_field1) {
    // ::std::option::Option::Some(::std::cmp::Ordering::Equal) =>
    // match ::std::cmp::PartialOrd::partial_cmp(&self_field2, &other_field2) {
    // ::std::option::Option::Some(::std::cmp::Ordering::Equal) => {
    // ...
    // }
    // cmp => cmp
    // },
    // cmp => cmp
    // }
    //
    cs_fold(// foldr nests the if-elses correctly, leaving the first field
            // as the outermost one, and the last as the innermost.
            false,
            |cx, span, old, self_f, other_fs| {
                // match new {
                //     Some(::std::cmp::Ordering::Equal) => old,
                //     cmp => cmp
                // }

                let new = {
                    let other_f = match (other_fs.len(), other_fs.get(0)) {
                        (1, Some(o_f)) => o_f,
                                _ => {
                                    cx.span_bug(span,
                                        "not exactly 2 arguments in `derive(PartialOrd)`")
                                }
                    };

                    let args = vec![
                            cx.expr_addr_of(span, self_f),
                            cx.expr_addr_of(span, other_f.clone()),
                        ];

                    cx.expr_call_global(span, partial_cmp_path.clone(), args)
                };

                let eq_arm = cx.arm(span,
                                    vec![cx.pat_some(span, cx.pat_path(span, ordering.clone()))],
                                    old);
                let neq_arm = cx.arm(span,
                                    vec![cx.pat_ident(span, test_id)],
                                    cx.expr_ident(span, test_id));

                cx.expr_match(span, new, vec![eq_arm, neq_arm])
            },
            equals_expr.clone(),
            Box::new(|cx, span, (self_args, tag_tuple), _non_self_args| {
        if self_args.len() != 2 {
            cx.span_bug(span, "not exactly 2 arguments in `derive(PartialOrd)`")
        } else {
            some_ordering_collapsed(cx, span, PartialCmpOp, tag_tuple)
        }
    }),
            cx,
            span,
            substr)
}

/// Strict inequality.
fn cs_op(less: bool,
         inclusive: bool,
         cx: &mut ExtCtxt,
         span: Span,
         substr: &Substructure) -> P<Expr> {
    let ordering_path = |cx: &mut ExtCtxt, name: &str| {
        cx.expr_path(cx.path_global(span, cx.std_path(&["cmp", "Ordering", name])))
    };

    let par_cmp = |cx: &mut ExtCtxt, span, self_f: P<Expr>, other_fs: &[P<Expr>], default| {
        let other_f = match (other_fs.len(), other_fs.get(0)) {
            (1, Some(o_f)) => o_f,
            _ => cx.span_bug(span, "not exactly 2 arguments in `derive(PartialOrd)`"),
        };

        // `PartialOrd::partial_cmp(self.fi, other.fi)`
        let cmp_path = cx.expr_path(cx.path_global(span, cx.std_path(&["cmp",
                                                                       "PartialOrd",
                                                                       "partial_cmp"])));
        let cmp = cx.expr_call(span,
                               cmp_path,
                               vec![cx.expr_addr_of(span, self_f),
                                    cx.expr_addr_of(span, other_f.clone())]);

        let default = ordering_path(cx, default);
        // `Option::unwrap_or(_, Ordering::Equal)`
        let unwrap_path = cx.expr_path(cx.path_global(span, cx.std_path(&["option",
                                                                          "Option",
                                                                          "unwrap_or"])));
        cx.expr_call(span, unwrap_path, vec![cmp, default])
    };

    let fold = cs_fold1(false, // need foldr
        |cx, span, subexpr, self_f, other_fs| {
            // build up a series of `partial_cmp`s from the inside
            // out (hence foldr) to get lexical ordering, i.e. for op ==
            // `ast::lt`
            //
            // ```
            // Ordering::then_with(
            //    Option::unwrap_or(
            //        PartialOrd::partial_cmp(self.f1, other.f1), Ordering::Equal)
            //    ),
            //    Option::unwrap_or(
            //        PartialOrd::partial_cmp(self.f2, other.f2), Ordering::Greater)
            //    )
            // )
            // == Ordering::Less
            // ```
            //
            // and for op ==
            // `ast::le`
            //
            // ```
            // Ordering::then_with(
            //    Option::unwrap_or(
            //        PartialOrd::partial_cmp(self.f1, other.f1), Ordering::Equal)
            //    ),
            //    Option::unwrap_or(
            //        PartialOrd::partial_cmp(self.f2, other.f2), Ordering::Greater)
            //    )
            // )
            // != Ordering::Greater
            // ```
            //
            // The optimiser should remove the redundancy. We explicitly
            // get use the binops to avoid auto-deref dereferencing too many
            // layers of pointers, if the type includes pointers.

            // `Option::unwrap_or(PartialOrd::partial_cmp(self.fi, other.fi), Ordering::Equal)`
            let par_cmp = par_cmp(cx, span, self_f, other_fs, "Equal");

            // `Ordering::then_with(Option::unwrap_or(..), ..)`
            let then_with_path = cx.expr_path(cx.path_global(span,
                                                             cx.std_path(&["cmp",
                                                                           "Ordering",
                                                                           "then_with"])));
            cx.expr_call(span, then_with_path, vec![par_cmp, cx.lambda0(span, subexpr)])
        },
        |cx, args| {
            match args {
                Some((span, self_f, other_fs)) => {
                    let opposite = if less { "Greater" } else { "Less" };
                    par_cmp(cx, span, self_f, other_fs, opposite)
                },
                None => cx.expr_bool(span, inclusive)
            }
        },
        Box::new(|cx, span, (self_args, tag_tuple), _non_self_args| {
            if self_args.len() != 2 {
                cx.span_bug(span, "not exactly 2 arguments in `derive(PartialOrd)`")
            } else {
                let op = match (less, inclusive) {
                    (false, false) => GtOp,
                    (false, true) => GeOp,
                    (true, false) => LtOp,
                    (true, true) => LeOp,
                };
                some_ordering_collapsed(cx, span, op, tag_tuple)
            }
        }),
        cx,
        span,
        substr);

    match *substr.fields {
        EnumMatching(.., ref all_fields) |
        Struct(.., ref all_fields) if !all_fields.is_empty() => {
            let ordering = ordering_path(cx, if less ^ inclusive { "Less" } else { "Greater" });
            let comp_op = if inclusive { BinOpKind::Ne } else { BinOpKind::Eq };

            cx.expr_binary(span, comp_op, fold, ordering)
        }
        _ => fold
    }
}
Commit	Line	Data
d9579d0f AL	1	// Copyright 2013 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.
	4	//
	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.
	10
	11	pub use self::OrderingOp::*;
	12
ff7c6d11	13	use deriving::{path_local, pathvec_std, path_std};
9cc50fc6 SL	14	use deriving::generic::*;
	15	use deriving::generic::ty::*;
	16
5bcae85e SL	17	use syntax::ast::{self, BinOpKind, Expr, MetaItem};
5bcae85e SL	18	use syntax::ext::base::{Annotatable, ExtCtxt};
9cc50fc6	19	use syntax::ext::build::AstBuilder;
9cc50fc6	20	use syntax::ptr::P;
476ff2be	21	use syntax::symbol::Symbol;
3157f602	22	use syntax_pos::Span;
d9579d0f AL	23
	24	pub fn expand_deriving_partial_ord(cx: &mut ExtCtxt,
	25	span: Span,
	26	mitem: &MetaItem,
62682a34	27	item: &Annotatable,
5bcae85e	28	push: &mut FnMut(Annotatable)) {
d9579d0f AL	29	macro_rules! md {
d9579d0f AL	30	($name:expr, $op:expr, $equal:expr) => { {
476ff2be	31	let inline = cx.meta_word(span, Symbol::intern("inline"));
c30ab7b3	32	let attrs = vec![cx.attribute(span, inline)];
d9579d0f AL	33	MethodDef {
	34	name: $name,
	35	generics: LifetimeBounds::empty(),
	36	explicit_self: borrowed_explicit_self(),
83c7162d	37	args: vec![(borrowed_self(), "other")],
d9579d0f AL	38	ret_ty: Literal(path_local!(bool)),
d9579d0f AL	39	attributes: attrs,
62682a34	40	is_unsafe: false,
a7813a04	41	unify_fieldless_variants: true,
d9579d0f AL	42	combine_substructure: combine_substructure(Box::new(\|cx, span, substr\| {
	43	cs_op($op, $equal, cx, span, substr)
	44	}))
	45	}
	46	} }
	47	}
	48
ff7c6d11 XL	49	let ordering_ty = Literal(path_std!(cx, cmp::Ordering));
ff7c6d11 XL	50	let ret_ty = Literal(Path::new_(pathvec_std!(cx, option::Option),
d9579d0f AL	51	None,
d9579d0f AL	52	vec![Box::new(ordering_ty)],
ff7c6d11	53	PathKind::Std));
d9579d0f	54
476ff2be	55	let inline = cx.meta_word(span, Symbol::intern("inline"));
5bcae85e	56	let attrs = vec![cx.attribute(span, inline)];
d9579d0f AL	57
	58	let partial_cmp_def = MethodDef {
	59	name: "partial_cmp",
	60	generics: LifetimeBounds::empty(),
	61	explicit_self: borrowed_explicit_self(),
83c7162d	62	args: vec![(borrowed_self(), "other")],
3b2f2976	63	ret_ty,
d9579d0f	64	attributes: attrs,
62682a34	65	is_unsafe: false,
a7813a04	66	unify_fieldless_variants: true,
d9579d0f AL	67	combine_substructure: combine_substructure(Box::new(\|cx, span, substr\| {
d9579d0f AL	68	cs_partial_cmp(cx, span, substr)
5bcae85e	69	})),
d9579d0f AL	70	};
d9579d0f AL	71
54a0048b SL	72	// avoid defining extra methods if we can
	73	// c-like enums, enums without any fields and structs without fields
	74	// can safely define only `partial_cmp`.
	75	let methods = if is_type_without_fields(item) {
	76	vec![partial_cmp_def]
	77	} else {
5bcae85e SL	78	vec![partial_cmp_def,
	79	md!("lt", true, false),
	80	md!("le", true, true),
	81	md!("gt", false, false),
	82	md!("ge", false, true)]
54a0048b SL	83	};
54a0048b SL	84
d9579d0f	85	let trait_def = TraitDef {
3b2f2976	86	span,
d9579d0f	87	attributes: vec![],
ff7c6d11	88	path: path_std!(cx, cmp::PartialOrd),
d9579d0f AL	89	additional_bounds: vec![],
d9579d0f AL	90	generics: LifetimeBounds::empty(),
e9174d1e	91	is_unsafe: false,
9e0c209e	92	supports_unions: false,
3b2f2976	93	methods,
d9579d0f AL	94	associated_types: Vec::new(),
d9579d0f AL	95	};
62682a34	96	trait_def.expand(cx, mitem, item, push)
d9579d0f AL	97	}
	98
	99	#[derive(Copy, Clone)]
	100	pub enum OrderingOp {
5bcae85e SL	101	PartialCmpOp,
	102	LtOp,
	103	LeOp,
	104	GtOp,
	105	GeOp,
d9579d0f AL	106	}
	107
	108	pub fn some_ordering_collapsed(cx: &mut ExtCtxt,
	109	span: Span,
	110	op: OrderingOp,
5bcae85e SL	111	self_arg_tags: &[ast::Ident])
5bcae85e SL	112	-> P<ast::Expr> {
d9579d0f AL	113	let lft = cx.expr_ident(span, self_arg_tags[0]);
	114	let rgt = cx.expr_addr_of(span, cx.expr_ident(span, self_arg_tags[1]));
	115	let op_str = match op {
	116	PartialCmpOp => "partial_cmp",
5bcae85e SL	117	LtOp => "lt",
	118	LeOp => "le",
	119	GtOp => "gt",
	120	GeOp => "ge",
d9579d0f AL	121	};
	122	cx.expr_method_call(span, lft, cx.ident_of(op_str), vec![rgt])
	123	}
	124
5bcae85e	125	pub fn cs_partial_cmp(cx: &mut ExtCtxt, span: Span, substr: &Substructure) -> P<Expr> {
83c7162d	126	let test_id = cx.ident_of("cmp").gensym();
5bcae85e	127	let ordering = cx.path_global(span, cx.std_path(&["cmp", "Ordering", "Equal"]));
54a0048b SL	128	let ordering_expr = cx.expr_path(ordering.clone());
54a0048b SL	129	let equals_expr = cx.expr_some(span, ordering_expr);
d9579d0f	130
e9174d1e	131	let partial_cmp_path = cx.std_path(&["cmp", "PartialOrd", "partial_cmp"]);
d9579d0f	132
5bcae85e SL	133	// Builds:
	134	//
	135	// match ::std::cmp::PartialOrd::partial_cmp(&self_field1, &other_field1) {
	136	// ::std::option::Option::Some(::std::cmp::Ordering::Equal) =>
	137	// match ::std::cmp::PartialOrd::partial_cmp(&self_field2, &other_field2) {
	138	// ::std::option::Option::Some(::std::cmp::Ordering::Equal) => {
	139	// ...
	140	// }
83c7162d	141	// cmp => cmp
5bcae85e	142	// },
83c7162d	143	// cmp => cmp
5bcae85e SL	144	// }
	145	//
	146	cs_fold(// foldr nests the if-elses correctly, leaving the first field
	147	// as the outermost one, and the last as the innermost.
	148	false,
	149	\|cx, span, old, self_f, other_fs\| {
94b46f34 XL	150	// match new {
	151	// Some(::std::cmp::Ordering::Equal) => old,
	152	// cmp => cmp
	153	// }
5bcae85e	154
94b46f34 XL	155	let new = {
	156	let other_f = match (other_fs.len(), other_fs.get(0)) {
	157	(1, Some(o_f)) => o_f,
	158	_ => {
	159	cx.span_bug(span,
	160	"not exactly 2 arguments in `derive(PartialOrd)`")
	161	}
	162	};
5bcae85e	163
94b46f34 XL	164	let args = vec![
	165	cx.expr_addr_of(span, self_f),
	166	cx.expr_addr_of(span, other_f.clone()),
	167	];
d9579d0f	168
94b46f34 XL	169	cx.expr_call_global(span, partial_cmp_path.clone(), args)
94b46f34 XL	170	};
5bcae85e	171
94b46f34 XL	172	let eq_arm = cx.arm(span,
	173	vec![cx.pat_some(span, cx.pat_path(span, ordering.clone()))],
	174	old);
	175	let neq_arm = cx.arm(span,
	176	vec![cx.pat_ident(span, test_id)],
	177	cx.expr_ident(span, test_id));
5bcae85e	178
94b46f34 XL	179	cx.expr_match(span, new, vec![eq_arm, neq_arm])
94b46f34 XL	180	},
5bcae85e SL	181	equals_expr.clone(),
	182	Box::new(\|cx, span, (self_args, tag_tuple), _non_self_args\| {
	183	if self_args.len() != 2 {
	184	cx.span_bug(span, "not exactly 2 arguments in `derive(PartialOrd)`")
	185	} else {
	186	some_ordering_collapsed(cx, span, PartialCmpOp, tag_tuple)
	187	}
	188	}),
	189	cx,
	190	span,
	191	substr)
d9579d0f AL	192	}
	193
	194	/// Strict inequality.
94b46f34 XL	195	fn cs_op(less: bool,
	196	inclusive: bool,
	197	cx: &mut ExtCtxt,
	198	span: Span,
	199	substr: &Substructure) -> P<Expr> {
	200	let ordering_path = \|cx: &mut ExtCtxt, name: &str\| {
	201	cx.expr_path(cx.path_global(span, cx.std_path(&["cmp", "Ordering", name])))
	202	};
	203
	204	let par_cmp = \|cx: &mut ExtCtxt, span, self_f: P<Expr>, other_fs: &[P<Expr>], default\| {
	205	let other_f = match (other_fs.len(), other_fs.get(0)) {
	206	(1, Some(o_f)) => o_f,
	207	_ => cx.span_bug(span, "not exactly 2 arguments in `derive(PartialOrd)`"),
	208	};
	209
	210	// `PartialOrd::partial_cmp(self.fi, other.fi)`
	211	let cmp_path = cx.expr_path(cx.path_global(span, cx.std_path(&["cmp",
	212	"PartialOrd",
	213	"partial_cmp"])));
	214	let cmp = cx.expr_call(span,
	215	cmp_path,
	216	vec![cx.expr_addr_of(span, self_f),
	217	cx.expr_addr_of(span, other_f.clone())]);
	218
	219	let default = ordering_path(cx, default);
	220	// `Option::unwrap_or(_, Ordering::Equal)`
	221	let unwrap_path = cx.expr_path(cx.path_global(span, cx.std_path(&["option",
	222	"Option",
	223	"unwrap_or"])));
	224	cx.expr_call(span, unwrap_path, vec![cmp, default])
	225	};
	226
	227	let fold = cs_fold1(false, // need foldr
83c7162d	228	\|cx, span, subexpr, self_f, other_fs\| {
94b46f34	229	// build up a series of `partial_cmp`s from the inside
83c7162d XL	230	// out (hence foldr) to get lexical ordering, i.e. for op ==
	231	// `ast::lt`
	232	//
	233	// ```
94b46f34 XL	234	// Ordering::then_with(
	235	// Option::unwrap_or(
	236	// PartialOrd::partial_cmp(self.f1, other.f1), Ordering::Equal)
	237	// ),
	238	// Option::unwrap_or(
	239	// PartialOrd::partial_cmp(self.f2, other.f2), Ordering::Greater)
	240	// )
83c7162d	241	// )
94b46f34	242	// == Ordering::Less
83c7162d XL	243	// ```
	244	//
	245	// and for op ==
	246	// `ast::le`
	247	//
	248	// ```
94b46f34 XL	249	// Ordering::then_with(
	250	// Option::unwrap_or(
	251	// PartialOrd::partial_cmp(self.f1, other.f1), Ordering::Equal)
	252	// ),
	253	// Option::unwrap_or(
	254	// PartialOrd::partial_cmp(self.f2, other.f2), Ordering::Greater)
	255	// )
83c7162d	256	// )
94b46f34	257	// != Ordering::Greater
83c7162d XL	258	// ```
	259	//
	260	// The optimiser should remove the redundancy. We explicitly
	261	// get use the binops to avoid auto-deref dereferencing too many
	262	// layers of pointers, if the type includes pointers.
5bcae85e	263
94b46f34 XL	264	// `Option::unwrap_or(PartialOrd::partial_cmp(self.fi, other.fi), Ordering::Equal)`
94b46f34 XL	265	let par_cmp = par_cmp(cx, span, self_f, other_fs, "Equal");
5bcae85e	266
94b46f34 XL	267	// `Ordering::then_with(Option::unwrap_or(..), ..)`
	268	let then_with_path = cx.expr_path(cx.path_global(span,
	269	cx.std_path(&["cmp",
	270	"Ordering",
	271	"then_with"])));
	272	cx.expr_call(span, then_with_path, vec![par_cmp, cx.lambda0(span, subexpr)])
83c7162d XL	273	},
	274	\|cx, args\| {
	275	match args {
	276	Some((span, self_f, other_fs)) => {
94b46f34 XL	277	let opposite = if less { "Greater" } else { "Less" };
	278	par_cmp(cx, span, self_f, other_fs, opposite)
	279	},
	280	None => cx.expr_bool(span, inclusive)
83c7162d XL	281	}
	282	},
	283	Box::new(\|cx, span, (self_args, tag_tuple), _non_self_args\| {
	284	if self_args.len() != 2 {
	285	cx.span_bug(span, "not exactly 2 arguments in `derive(PartialOrd)`")
	286	} else {
94b46f34	287	let op = match (less, inclusive) {
83c7162d XL	288	(false, false) => GtOp,
	289	(false, true) => GeOp,
	290	(true, false) => LtOp,
	291	(true, true) => LeOp,
	292	};
	293	some_ordering_collapsed(cx, span, op, tag_tuple)
	294	}
	295	}),
	296	cx,
	297	span,
94b46f34 XL	298	substr);
	299
	300	match *substr.fields {
	301	EnumMatching(.., ref all_fields) \|
	302	Struct(.., ref all_fields) if !all_fields.is_empty() => {
	303	let ordering = ordering_path(cx, if less ^ inclusive { "Less" } else { "Greater" });
	304	let comp_op = if inclusive { BinOpKind::Ne } else { BinOpKind::Eq };
	305
	306	cx.expr_binary(span, comp_op, fold, ordering)
	307	}
	308	_ => fold
	309	}
d9579d0f	310	}