Split into modules
diff --git a/src/attr.rs b/src/attr.rs
new file mode 100644
index 0000000..1f329c7
--- /dev/null
+++ b/src/attr.rs
@@ -0,0 +1,65 @@
+use super::*;
+
+use common::word;
+use helper::escaped_string;
+
+#[derive(Debug, Clone, Eq, PartialEq)]
+pub struct Attribute {
+    pub value: MetaItem,
+    pub is_sugared_doc: bool,
+}
+
+/// A compile-time attribute item.
+///
+/// E.g. `#[test]`, `#[derive(..)]` or `#[feature = "foo"]`
+#[derive(Debug, Clone, Eq, PartialEq)]
+pub enum MetaItem {
+    /// Word meta item.
+    ///
+    /// E.g. `test` as in `#[test]`
+    Word(Ident),
+    /// List meta item.
+    ///
+    /// E.g. `derive(..)` as in `#[derive(..)]`
+    List(Ident, Vec<MetaItem>),
+    /// Name value meta item.
+    ///
+    /// E.g. `feature = "foo"` as in `#[feature = "foo"]`
+    NameValue(Ident, String),
+}
+
+named!(pub attribute<&str, Attribute>, chain!(
+    punct!("#") ~
+    punct!("[") ~
+    meta_item: meta_item ~
+    punct!("]"),
+    move || Attribute {
+        value: meta_item,
+        is_sugared_doc: false,
+    }
+));
+
+named!(quoted<&str, String>, delimited!(
+    punct!("\""),
+    escaped_string,
+    tag_s!("\"")
+));
+
+named!(meta_item<&str, MetaItem>, alt!(
+    chain!(
+        ident: word ~
+        punct!("(") ~
+        inner: separated_list!(punct!(","), meta_item) ~
+        punct!(")"),
+        move || MetaItem::List(ident, inner)
+    )
+    |
+    chain!(
+        ident: word ~
+        punct!("=") ~
+        string: quoted,
+        move || MetaItem::NameValue(ident, string)
+    )
+    |
+    map!(word, MetaItem::Word)
+));
diff --git a/src/common.rs b/src/common.rs
new file mode 100644
index 0000000..c7a2609
--- /dev/null
+++ b/src/common.rs
@@ -0,0 +1,25 @@
+pub type Ident = String;
+
+#[derive(Debug, Clone, Eq, PartialEq)]
+pub enum Visibility {
+    Public,
+    Inherited,
+}
+
+fn ident_ch(ch: char) -> bool {
+    ch.is_alphanumeric() || ch == '_'
+}
+
+named!(pub word<&str, Ident>, preceded!(
+    opt!(call!(::nom::multispace)),
+    map!(take_while1_s!(ident_ch), String::from)
+));
+
+named!(pub visibility<&str, Visibility>, preceded!(
+    opt!(call!(::nom::space)),
+    alt!(
+        terminated!(tag_s!("pub"), call!(::nom::multispace)) => { |_| Visibility::Public }
+        |
+        epsilon!() => { |_| Visibility::Inherited }
+    )
+));
diff --git a/src/generics.rs b/src/generics.rs
new file mode 100644
index 0000000..26c7d30
--- /dev/null
+++ b/src/generics.rs
@@ -0,0 +1,171 @@
+use super::*;
+
+use common::word;
+use ty::{ty, poly_trait_ref};
+use nom::multispace as space;
+
+#[derive(Debug, Clone, Eq, PartialEq, Default)]
+pub struct Generics {
+    pub lifetimes: Vec<LifetimeDef>,
+    pub ty_params: Vec<TyParam>,
+    pub where_clause: Vec<WherePredicate>,
+}
+
+#[derive(Debug, Clone, Eq, PartialEq)]
+pub struct Lifetime {
+    pub ident: Ident,
+}
+
+#[derive(Debug, Clone, Eq, PartialEq)]
+pub struct LifetimeDef {
+    pub lifetime: Lifetime,
+    pub bounds: Vec<Lifetime>,
+}
+
+#[derive(Debug, Clone, Eq, PartialEq)]
+pub struct TyParam {
+    pub ident: Ident,
+    pub bounds: Vec<TyParamBound>,
+    pub default: Option<Ty>,
+}
+
+#[derive(Debug, Clone, Eq, PartialEq)]
+pub enum TyParamBound {
+    MaybeSized,
+    Region(Lifetime),
+    Trait(PolyTraitRef),
+}
+
+/// A single predicate in a `where` clause
+#[derive(Debug, Clone, Eq, PartialEq)]
+pub enum WherePredicate {
+    /// A type binding, e.g. `for<'c> Foo: Send+Clone+'c`
+    BoundPredicate(WhereBoundPredicate),
+    /// A lifetime predicate, e.g. `'a: 'b+'c`
+    RegionPredicate(WhereRegionPredicate),
+}
+
+/// A type bound.
+///
+/// E.g. `for<'c> Foo: Send+Clone+'c`
+#[derive(Debug, Clone, Eq, PartialEq)]
+pub struct WhereBoundPredicate {
+    /// Any lifetimes from a `for` binding
+    pub bound_lifetimes: Vec<LifetimeDef>,
+    /// The type being bounded
+    pub bounded_ty: Ty,
+    /// Trait and lifetime bounds (`Clone+Send+'static`)
+    pub bounds: Vec<TyParamBound>,
+}
+
+/// A lifetime predicate.
+///
+/// E.g. `'a: 'b+'c`
+#[derive(Debug, Clone, Eq, PartialEq)]
+pub struct WhereRegionPredicate {
+    pub lifetime: Lifetime,
+    pub bounds: Vec<Lifetime>,
+}
+
+named!(pub generics<&str, Generics>, chain!(
+    bracketed: alt!(
+        chain!(
+            punct!("<") ~
+            lifetimes: separated_list!(punct!(","), lifetime_def) ~
+            ty_params: opt_vec!(preceded!(
+                cond!(!lifetimes.is_empty(), punct!(",")),
+                separated_nonempty_list!(punct!(","), ty_param)
+            )) ~
+            punct!(">"),
+            move || (lifetimes, ty_params)
+        )
+        |
+        epsilon!() => { |_| (Vec::new(), Vec::new()) }
+    ) ~
+    where_clause: opt_vec!(chain!(
+        punct!("where") ~
+        space ~
+        predicates: separated_nonempty_list!(punct!(","), where_predicate) ~
+        punct!(",")? ~
+        move || predicates
+    )),
+    move || Generics {
+        lifetimes: bracketed.0,
+        ty_params: bracketed.1,
+        where_clause: where_clause,
+    }
+));
+
+named!(pub lifetime<&str, Lifetime>, preceded!(
+    punct!("'"),
+    map!(word, |ident| Lifetime { ident: ident })
+));
+
+named!(pub lifetime_def<&str, LifetimeDef>, chain!(
+    life: lifetime ~
+    bounds: opt_vec!(preceded!(
+        punct!(":"),
+        separated_nonempty_list!(punct!(","), lifetime)
+    )),
+    move || LifetimeDef {
+        lifetime: life,
+        bounds: bounds,
+    }
+));
+
+named!(pub bound_lifetimes<&str, Vec<LifetimeDef> >, opt_vec!(chain!(
+    punct!("for") ~
+    punct!("<") ~
+    lifetimes: separated_list!(punct!(","), lifetime_def) ~
+    punct!(">"),
+    move || lifetimes
+)));
+
+named!(ty_param<&str, TyParam>, chain!(
+    ident: word ~
+    bounds: opt_vec!(preceded!(
+        punct!(":"),
+        separated_nonempty_list!(punct!("+"), ty_param_bound)
+    )) ~
+    default: opt!(preceded!(
+        punct!("="),
+        ty
+    )) ~
+    move || TyParam {
+        ident: ident,
+        bounds: bounds,
+        default: default,
+    }
+));
+
+named!(pub ty_param_bound<&str, TyParamBound>, alt!(
+    tuple!(punct!("?"), punct!("Sized")) => { |_| TyParamBound::MaybeSized }
+    |
+    lifetime => { TyParamBound::Region }
+    |
+    poly_trait_ref => { TyParamBound::Trait }
+));
+
+named!(where_predicate<&str, WherePredicate>, alt!(
+    chain!(
+        ident: lifetime ~
+        punct!(":") ~
+        bounds: separated_nonempty_list!(punct!("+"), lifetime),
+        move || WherePredicate::RegionPredicate(WhereRegionPredicate {
+            lifetime: ident,
+            bounds: bounds,
+        })
+    )
+    |
+    chain!(
+        bound_lifetimes: bound_lifetimes ~
+        bounded_ty: ty ~
+        punct!(":") ~
+        bounds: separated_nonempty_list!(punct!("+"), ty_param_bound),
+        move || WherePredicate::BoundPredicate(WhereBoundPredicate {
+            bound_lifetimes: bound_lifetimes,
+            bounded_ty: bounded_ty,
+            bounds: bounds,
+        })
+    )
+));
diff --git a/src/helper.rs b/src/helper.rs
new file mode 100644
index 0000000..5299cc4
--- /dev/null
+++ b/src/helper.rs
@@ -0,0 +1,65 @@
+use nom::{self, IResult};
+
+macro_rules! punct {
+    ($i:expr, $punct:expr) => {
+        tuple!($i, opt!(call!(::nom::multispace)), tag_s!($punct))
+    };
+}
+
+macro_rules! opt_vec (
+    ($i:expr, $submac:ident!( $($args:tt)* )) => ({
+        match $submac!($i, $($args)*) {
+            ::nom::IResult::Done(i, o) => ::nom::IResult::Done(i, o),
+            ::nom::IResult::Error(_) => ::nom::IResult::Done($i, Vec::new()),
+            ::nom::IResult::Incomplete(i) => ::nom::IResult::Incomplete(i)
+        }
+    });
+);
+
+macro_rules! epsilon {
+    ($i:expr,) => {
+        call!($i, {
+            fn epsilon<T>(input: T) -> ::nom::IResult<T, ()> {
+                ::nom::IResult::Done(input, ())
+            }
+            epsilon
+        })
+    };
+}
+
+pub fn escaped_string(input: &str) -> IResult<&str, String> {
+    let mut s = String::new();
+    let mut chars = input.char_indices().peekable();
+    while let Some((byte_offset, ch)) = chars.next() {
+        match ch {
+            '"' => {
+                return IResult::Done(&input[byte_offset..], s);
+            }
+            '\\' => {
+                match chars.next() {
+                    Some((_, 'x')) => unimplemented!(),
+                    Some((_, 'u')) => unimplemented!(),
+                    Some((_, 'n')) => s.push('\n'),
+                    Some((_, 'r')) => s.push('\r'),
+                    Some((_, 't')) => s.push('\t'),
+                    Some((_, '0')) => s.push('\0'),
+                    Some((_, '\\')) => s.push('\\'),
+                    Some((_, '\n')) => {
+                        while let Some(&(_, ch)) = chars.peek() {
+                            if ch.is_whitespace() {
+                                chars.next();
+                            } else {
+                                break;
+                            }
+                        }
+                    }
+                    _ => break,
+                }
+            }
+            ch => {
+                s.push(ch);
+            }
+        }
+    }
+    IResult::Error(nom::Err::Position(nom::ErrorKind::Escaped, input))
+}
diff --git a/src/item.rs b/src/item.rs
new file mode 100644
index 0000000..a1d8358
--- /dev/null
+++ b/src/item.rs
@@ -0,0 +1,149 @@
+use super::*;
+
+use attr::attribute;
+use common::{word, visibility};
+use generics::generics;
+use ty::ty;
+use nom::multispace as space;
+
+#[derive(Debug, Clone, Eq, PartialEq)]
+pub struct Item {
+    pub ident: Ident,
+    pub vis: Visibility,
+    pub attrs: Vec<Attribute>,
+    pub generics: Generics,
+    pub body: Body,
+}
+
+#[derive(Debug, Clone, Eq, PartialEq)]
+pub enum Body {
+    Enum(Vec<Variant>),
+    Struct(Style, Vec<Field>),
+}
+
+#[derive(Debug, Clone, Eq, PartialEq)]
+pub struct Variant {
+    pub ident: Ident,
+    pub attrs: Vec<Attribute>,
+    pub style: Style,
+    pub fields: Vec<Field>,
+}
+
+#[derive(Debug, Clone, Eq, PartialEq)]
+pub enum Style {
+    Struct,
+    Tuple,
+    Unit,
+}
+
+#[derive(Debug, Clone, Eq, PartialEq)]
+pub struct Field {
+    pub ident: Option<Ident>,
+    pub vis: Visibility,
+    pub attrs: Vec<Attribute>,
+    pub ty: Ty,
+}
+
+named!(pub item<&str, Item>, chain!(
+    attrs: many0!(attribute) ~
+    vis: visibility ~
+    which: alt!(tag_s!("struct") | tag_s!("enum")) ~
+    space ~
+    ident: word ~
+    generics: generics ~
+    item: switch!(value!(which),
+        "struct" => map!(struct_body, move |(style, fields)| Item {
+            ident: ident,
+            vis: vis,
+            attrs: attrs,
+            generics: generics,
+            body: Body::Struct(style, fields),
+        })
+        |
+        "enum" => map!(enum_body, move |body| Item {
+            ident: ident,
+            vis: vis,
+            attrs: attrs,
+            generics: generics,
+            body: body,
+        })
+    ) ~
+    space?,
+    move || item
+));
+
+named!(struct_body<&str, (Style, Vec<Field>)>, alt!(
+    struct_like_body => { |fields| (Style::Struct, fields) }
+    |
+    terminated!(tuple_like_body, punct!(";")) => { |fields| (Style::Tuple, fields) }
+    |
+    punct!(";") => { |_| (Style::Unit, Vec::new()) }
+));
+
+named!(enum_body<&str, Body>, chain!(
+    punct!("{") ~
+    variants: separated_list!(punct!(","), variant) ~
+    punct!(",")? ~
+    punct!("}"),
+    move || Body::Enum(variants)
+));
+
+named!(variant<&str, Variant>, chain!(
+    attrs: many0!(attribute) ~
+    ident: word ~
+    body: alt!(
+        struct_like_body => { |fields| (Style::Struct, fields) }
+        |
+        tuple_like_body => { |fields| (Style::Tuple, fields) }
+        |
+        epsilon!() => { |_| (Style::Unit, Vec::new()) }
+    ),
+    move || Variant {
+        ident: ident,
+        attrs: attrs,
+        style: body.0,
+        fields: body.1,
+    }
+));
+
+named!(struct_like_body<&str, Vec<Field> >, chain!(
+    punct!("{") ~
+    fields: separated_list!(punct!(","), struct_field) ~
+    punct!(",")? ~
+    punct!("}"),
+    move || fields
+));
+
+named!(tuple_like_body<&str, Vec<Field> >, chain!(
+    punct!("(") ~
+    fields: separated_list!(punct!(","), tuple_field) ~
+    punct!(",")? ~
+    punct!(")"),
+    move || fields
+));
+
+named!(struct_field<&str, Field>, chain!(
+    attrs: many0!(attribute) ~
+    vis: visibility ~
+    ident: word ~
+    punct!(":") ~
+    ty: ty,
+    move || Field {
+        ident: Some(ident),
+        vis: vis,
+        attrs: attrs,
+        ty: ty,
+    }
+));
+
+named!(tuple_field<&str, Field>, chain!(
+    attrs: many0!(attribute) ~
+    vis: visibility ~
+    ty: ty,
+    move || Field {
+        ident: None,
+        vis: vis,
+        attrs: attrs,
+        ty: ty,
+    }
+));
diff --git a/src/lib.rs b/src/lib.rs
index 4d82a40..de2418c 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -1,849 +1,72 @@
 #[macro_use]
 extern crate nom;
 
-use nom::IResult;
-use nom::{digit, multispace as space};
+#[macro_use]
+mod helper;
 
-use std::str;
+mod attr;
+pub use attr::{
+    Attribute,
+    MetaItem,
+};
 
-#[derive(Debug, Clone, Eq, PartialEq)]
-pub struct Item {
-    pub ident: Ident,
-    pub vis: Visibility,
-    pub attrs: Vec<Attribute>,
-    pub generics: Generics,
-    pub body: Body,
-}
+mod common;
+pub use common::{
+    Ident,
+    Visibility,
+};
 
-pub type Ident = String;
+mod generics;
+pub use generics::{
+    Generics,
+    Lifetime,
+    LifetimeDef,
+    TyParam,
+    TyParamBound,
+    WhereBoundPredicate,
+    WherePredicate,
+    WhereRegionPredicate,
+};
 
-#[derive(Debug, Clone, Eq, PartialEq)]
-pub struct Attribute {
-    pub value: MetaItem,
-    pub is_sugared_doc: bool,
-}
+mod item;
+pub use item::{
+    Body,
+    Field,
+    Item,
+    Style,
+    Variant,
+};
 
-/// A compile-time attribute item.
-///
-/// E.g. `#[test]`, `#[derive(..)]` or `#[feature = "foo"]`
-#[derive(Debug, Clone, Eq, PartialEq)]
-pub enum MetaItem {
-    /// Word meta item.
-    ///
-    /// E.g. `test` as in `#[test]`
-    Word(Ident),
-    /// List meta item.
-    ///
-    /// E.g. `derive(..)` as in `#[derive(..)]`
-    List(Ident, Vec<MetaItem>),
-    /// Name value meta item.
-    ///
-    /// E.g. `feature = "foo"` as in `#[feature = "foo"]`
-    NameValue(Ident, String),
-}
-
-#[derive(Debug, Clone, Eq, PartialEq, Default)]
-pub struct Generics {
-    pub lifetimes: Vec<LifetimeDef>,
-    pub ty_params: Vec<TyParam>,
-    pub where_clause: Vec<WherePredicate>,
-}
-
-/// A single predicate in a `where` clause
-#[derive(Debug, Clone, Eq, PartialEq)]
-pub enum WherePredicate {
-    /// A type binding, e.g. `for<'c> Foo: Send+Clone+'c`
-    BoundPredicate(WhereBoundPredicate),
-    /// A lifetime predicate, e.g. `'a: 'b+'c`
-    RegionPredicate(WhereRegionPredicate),
-}
-
-/// A type bound.
-///
-/// E.g. `for<'c> Foo: Send+Clone+'c`
-#[derive(Debug, Clone, Eq, PartialEq)]
-pub struct WhereBoundPredicate {
-    /// Any lifetimes from a `for` binding
-    pub bound_lifetimes: Vec<LifetimeDef>,
-    /// The type being bounded
-    pub bounded_ty: Ty,
-    /// Trait and lifetime bounds (`Clone+Send+'static`)
-    pub bounds: Vec<TyParamBound>,
-}
-
-/// A lifetime predicate.
-///
-/// E.g. `'a: 'b+'c`
-#[derive(Debug, Clone, Eq, PartialEq)]
-pub struct WhereRegionPredicate {
-    pub lifetime: Lifetime,
-    pub bounds: Vec<Lifetime>,
-}
-
-#[derive(Debug, Clone, Eq, PartialEq)]
-pub struct LifetimeDef {
-    pub lifetime: Lifetime,
-    pub bounds: Vec<Lifetime>,
-}
-
-#[derive(Debug, Clone, Eq, PartialEq)]
-pub struct Lifetime {
-    pub ident: Ident,
-}
-
-#[derive(Debug, Clone, Eq, PartialEq)]
-pub struct TyParam {
-    pub ident: Ident,
-    pub bounds: Vec<TyParamBound>,
-    pub default: Option<Ty>,
-}
-
-#[derive(Debug, Clone, Eq, PartialEq)]
-pub enum TyParamBound {
-    MaybeSized,
-    Region(Lifetime),
-    Trait(PolyTraitRef),
-}
-
-#[derive(Debug, Clone, Eq, PartialEq)]
-pub struct PolyTraitRef {
-    /// The `'a` in `<'a> Foo<&'a T>`
-    pub bound_lifetimes: Vec<LifetimeDef>,
-    /// The `Foo<&'a T>` in `<'a> Foo<&'a T>`
-    pub trait_ref: Path,
-}
-
-#[derive(Debug, Clone, Eq, PartialEq)]
-pub struct Path {
-    pub global: bool,
-    pub segments: Vec<PathSegment>,
-}
-
-/// A segment of a path: an identifier, an optional lifetime, and a set of types.
-///
-/// E.g. `std`, `String` or `Box<T>`
-#[derive(Debug, Clone, Eq, PartialEq)]
-pub struct PathSegment {
-    pub ident: Ident,
-    pub parameters: PathParameters,
-}
-
-impl PathSegment {
-    pub fn ident(ident: Ident) -> Self {
-        PathSegment {
-            ident: ident,
-            parameters: PathParameters::none(),
-        }
-    }
-}
-
-/// Parameters of a path segment.
-///
-/// E.g. `<A, B>` as in `Foo<A, B>` or `(A, B)` as in `Foo(A, B)`
-#[derive(Debug, Clone, Eq, PartialEq)]
-pub enum PathParameters {
-    /// The `<'a, A, B, C>` in `foo::bar::baz::<'a, A, B, C>`
-    AngleBracketed(AngleBracketedParameterData),
-    /// The `(A, B)` and `C` in `Foo(A, B) -> C`
-    Parenthesized(ParenthesizedParameterData),
-}
-
-impl PathParameters {
-    pub fn none() -> Self {
-        PathParameters::AngleBracketed(AngleBracketedParameterData::default())
-    }
-}
-
-/// A path like `Foo<'a, T>`
-#[derive(Debug, Clone, Eq, PartialEq, Default)]
-pub struct AngleBracketedParameterData {
-    /// The lifetime parameters for this path segment.
-    pub lifetimes: Vec<Lifetime>,
-    /// The type parameters for this path segment, if present.
-    pub types: Vec<Ty>,
-    /// Bindings (equality constraints) on associated types, if present.
-    ///
-    /// E.g., `Foo<A=Bar>`.
-    pub bindings: Vec<TypeBinding>,
-}
-
-/// Bind a type to an associated type: `A=Foo`.
-#[derive(Debug, Clone, Eq, PartialEq)]
-pub struct TypeBinding {
-    pub ident: Ident,
-    pub ty: Ty,
-}
-
-/// A path like `Foo(A,B) -> C`
-#[derive(Debug, Clone, Eq, PartialEq)]
-pub struct ParenthesizedParameterData {
-    /// `(A, B)`
-    pub inputs: Vec<Ty>,
-    /// `C`
-    pub output: Option<Ty>,
-}
-
-#[derive(Debug, Clone, Eq, PartialEq)]
-pub enum Body {
-    Enum(Vec<Variant>),
-    Struct(Style, Vec<Field>),
-}
-
-#[derive(Debug, Clone, Eq, PartialEq)]
-pub struct Variant {
-    pub ident: Ident,
-    pub attrs: Vec<Attribute>,
-    pub style: Style,
-    pub fields: Vec<Field>,
-}
-
-#[derive(Debug, Clone, Eq, PartialEq)]
-pub enum Style {
-    Struct,
-    Tuple,
-    Unit,
-}
-
-#[derive(Debug, Clone, Eq, PartialEq)]
-pub struct Field {
-    pub ident: Option<Ident>,
-    pub vis: Visibility,
-    pub attrs: Vec<Attribute>,
-    pub ty: Ty,
-}
-
-#[derive(Debug, Clone, Eq, PartialEq)]
-pub enum Visibility {
-    Public,
-    Inherited,
-}
-
-#[derive(Debug, Clone, Eq, PartialEq)]
-pub enum Ty {
-    /// A variable-length array (`[T]`)
-    Vec(Box<Ty>),
-    /// A fixed length array (`[T; n]`)
-    FixedLengthVec(Box<Ty>, usize),
-    /// A raw pointer (`*const T` or `*mut T`)
-    Ptr(Box<MutTy>),
-    /// A reference (`&'a T` or `&'a mut T`)
-    Rptr(Option<Lifetime>, Box<MutTy>),
-    /// A bare function (e.g. `fn(usize) -> bool`)
-    BareFn(Box<BareFnTy>),
-    /// The never type (`!`)
-    Never,
-    /// A tuple (`(A, B, C, D, ...)`)
-    Tup(Vec<Ty>),
-    /// A path (`module::module::...::Type`), optionally
-    /// "qualified", e.g. `<Vec<T> as SomeTrait>::SomeType`.
-    ///
-    /// Type parameters are stored in the Path itself
-    Path(Option<QSelf>, Path),
-    /// Something like `A+B`. Note that `B` must always be a path.
-    ObjectSum(Box<Ty>, Vec<TyParamBound>),
-    /// A type like `for<'a> Foo<&'a Bar>`
-    PolyTraitRef(Vec<TyParamBound>),
-    /// An `impl TraitA+TraitB` type.
-    ImplTrait(Vec<TyParamBound>),
-    /// No-op; kept solely so that we can pretty-print faithfully
-    Paren(Box<Ty>),
-    /// TyKind::Infer means the type should be inferred instead of it having been
-    /// specified. This can appear anywhere in a type.
-    Infer,
-}
-
-#[derive(Debug, Clone, Eq, PartialEq)]
-pub struct MutTy {
-    pub ty: Ty,
-    pub mutability: Mutability,
-}
-
-#[derive(Debug, Clone, Eq, PartialEq)]
-pub enum Mutability {
-    Mutable,
-    Immutable,
-}
-
-/// The explicit Self type in a "qualified path". The actual
-/// path, including the trait and the associated item, is stored
-/// separately. `position` represents the index of the associated
-/// item qualified with this Self type.
-///
-/// ```rust,ignore
-/// <Vec<T> as a::b::Trait>::AssociatedItem
-///  ^~~~~     ~~~~~~~~~~~~~~^
-///  ty        position = 3
-///
-/// <Vec<T>>::AssociatedItem
-///  ^~~~~    ^
-///  ty       position = 0
-/// ```
-#[derive(Debug, Clone, Eq, PartialEq)]
-pub struct QSelf {
-    pub ty: Box<Ty>,
-    pub position: usize
-}
-
-#[derive(Debug, Clone, Eq, PartialEq)]
-pub struct BareFnTy {
-    pub lifetimes: Vec<LifetimeDef>,
-    pub decl: FnDecl
-}
-
-/// Header (not the body) of a function declaration.
-///
-/// E.g. `fn foo(bar: baz)`
-#[derive(Debug, Clone, Eq, PartialEq)]
-pub struct FnDecl {
-    pub inputs: Vec<Arg>,
-    pub output: FunctionRetTy,
-}
-
-/// An argument in a function header.
-///
-/// E.g. `bar: usize` as in `fn foo(bar: usize)`
-#[derive(Debug, Clone, Eq, PartialEq)]
-pub struct Arg {
-    pub pat: Option<Ident>,
-    pub ty: Ty,
-}
-
-#[derive(Debug, Clone, Eq, PartialEq)]
-pub enum FunctionRetTy {
-    /// Return type is not specified.
-    ///
-    /// Functions default to `()` and
-    /// closures default to inference. Span points to where return
-    /// type would be inserted.
-    Default,
-    /// Everything else
-    Ty(Ty),
-}
-
-pub fn epsilon<T>(input: T) -> IResult<T, ()> {
-    IResult::Done(input, ())
-}
-
-pub fn escaped_string(input: &str) -> IResult<&str, String> {
-    let mut s = String::new();
-    let mut chars = input.char_indices().peekable();
-    while let Some((byte_offset, ch)) = chars.next() {
-        match ch {
-            '"' => {
-                return IResult::Done(&input[byte_offset..], s);
-            }
-            '\\' => {
-                match chars.next() {
-                    Some((_, 'x')) => unimplemented!(),
-                    Some((_, 'u')) => unimplemented!(),
-                    Some((_, 'n')) => s.push('\n'),
-                    Some((_, 'r')) => s.push('\r'),
-                    Some((_, 't')) => s.push('\t'),
-                    Some((_, '0')) => s.push('\0'),
-                    Some((_, '\\')) => s.push('\\'),
-                    Some((_, '\n')) => {
-                        while let Some(&(_, ch)) = chars.peek() {
-                            if ch.is_whitespace() {
-                                chars.next();
-                            } else {
-                                break;
-                            }
-                        }
-                    }
-                    _ => break,
-                }
-            }
-            ch => {
-                s.push(ch);
-            }
-        }
-    }
-    IResult::Error(nom::Err::Position(nom::ErrorKind::Escaped, input))
-}
-
-macro_rules! punct {
-    ($i:expr, $ch:expr) => {
-        tuple!($i, opt!(space), tag_s!($ch))
-    };
-}
-
-named!(quoted<&str, String>, delimited!(
-    punct!("\""),
-    escaped_string,
-    tag_s!("\"")
-));
-
-named!(meta_item<&str, MetaItem>, alt!(
-    chain!(
-        ident: word ~
-        punct!("(") ~
-        inner: separated_list!(punct!(","), meta_item) ~
-        punct!(")"),
-        move || MetaItem::List(ident, inner)
-    )
-    |
-    chain!(
-        ident: word ~
-        punct!("=") ~
-        string: quoted,
-        move || MetaItem::NameValue(ident, string)
-    )
-    |
-    map!(word, MetaItem::Word)
-));
-
-named!(attribute<&str, Attribute>, chain!(
-    punct!("#") ~
-    punct!("[") ~
-    meta_item: meta_item ~
-    punct!("]"),
-    move || Attribute {
-        value: meta_item,
-        is_sugared_doc: false,
-    }
-));
-
-named!(mutability<&str, Mutability>, preceded!(
-    opt!(space),
-    alt!(
-        terminated!(tag_s!("mut"), space) => { |_| Mutability::Mutable }
-        |
-        epsilon => { |_| Mutability::Immutable }
-    )
-));
-
-named!(visibility<&str, Visibility>, preceded!(
-    opt!(space),
-    alt!(
-        terminated!(tag_s!("pub"), space) => { |_| Visibility::Public }
-        |
-        epsilon => { |_| Visibility::Inherited }
-    )
-));
-
-fn ident_ch(ch: char) -> bool {
-    ch.is_alphanumeric() || ch == '_'
-}
-
-named!(word<&str, Ident>, preceded!(
-    opt!(space),
-    map!(take_while1_s!(ident_ch), String::from)
-));
-
-macro_rules! opt_vec (
-    ($i:expr, $submac:ident!( $($args:tt)* )) => ({
-        match $submac!($i, $($args)*) {
-            IResult::Done(i, o) => IResult::Done(i, o),
-            IResult::Error(_) => IResult::Done($i, Vec::new()),
-            IResult::Incomplete(i) => IResult::Incomplete(i)
-        }
-    });
-);
-
-named!(type_binding<&str, TypeBinding>, chain!(
-    ident: word ~
-    punct!("=") ~
-    ty: ty,
-    move || TypeBinding {
-        ident: ident,
-        ty: ty,
-    }
-));
-
-named!(path_segment<&str, PathSegment>, alt!(
-    chain!(
-        ident: word ~
-        punct!("<") ~
-        lifetimes: separated_list!(punct!(","), lifetime) ~
-        types: opt_vec!(preceded!(
-            cond!(!lifetimes.is_empty(), punct!(",")),
-            separated_nonempty_list!(
-                punct!(","),
-                terminated!(ty, not!(peek!(punct!("="))))
-            )
-        )) ~
-        bindings: opt_vec!(preceded!(
-            cond!(!lifetimes.is_empty() || !types.is_empty(), punct!(",")),
-            separated_nonempty_list!(punct!(","), type_binding)
-        )) ~
-        punct!(">"),
-        move || PathSegment {
-            ident: ident,
-            parameters: PathParameters::AngleBracketed(
-                AngleBracketedParameterData {
-                    lifetimes: lifetimes,
-                    types: types,
-                    bindings: bindings,
-                }
-            ),
-        }
-    )
-    |
-    map!(word, PathSegment::ident)
-));
-
-named!(path<&str, Path>, chain!(
-    global: punct!("::")? ~
-    segments: separated_nonempty_list!(punct!("::"), path_segment),
-    move || Path {
-        global: global.is_some(),
-        segments: segments,
-    }
-));
-
-named!(fn_arg<&str, Arg>, chain!(
-    pat: opt!(terminated!(word, punct!(":"))) ~
-    ty: ty,
-    move || Arg {
-        pat: pat,
-        ty: ty,
-    }
-));
-
-named!(ty<&str, Ty>, alt!(
-    delimited!(
-        punct!("["),
-        ty,
-        punct!("]")
-    ) => { |elem| Ty::Vec(Box::new(elem)) }
-    |
-    chain!(
-        punct!("[") ~
-        elem: ty ~
-        punct!(";") ~
-        space? ~
-        size: map_res!(digit, str::parse),
-        move || Ty::FixedLengthVec(Box::new(elem), size)
-    )
-    |
-    chain!(
-        punct!("*") ~
-        mutability: alt!(
-            punct!("const") => { |_| Mutability::Immutable }
-            |
-            punct!("mut") => { |_| Mutability::Mutable }
-        ) ~
-        target: ty,
-        move || Ty::Ptr(Box::new(MutTy {
-            ty: target,
-            mutability: mutability,
-        }))
-    )
-    |
-    chain!(
-        punct!("&") ~
-        life: lifetime? ~
-        mutability: mutability ~
-        target: ty,
-        move || Ty::Rptr(life, Box::new(MutTy {
-            ty: target,
-            mutability: mutability,
-        }))
-    )
-    |
-    chain!(
-        punct!("fn") ~
-        space ~
-        lifetimes: opt_vec!(delimited!(
-            punct!("<"),
-            separated_list!(punct!(","), lifetime_def),
-            punct!(">")
-        )) ~
-        punct!("(") ~
-        inputs: separated_list!(punct!(","), fn_arg) ~
-        punct!(")") ~
-        output: opt!(preceded!(
-            punct!("->"),
-            ty
-        )),
-        move || Ty::BareFn(Box::new(BareFnTy {
-            lifetimes: lifetimes,
-            decl: FnDecl {
-                inputs: inputs,
-                output: match output {
-                    Some(ty) => FunctionRetTy::Ty(ty),
-                    None => FunctionRetTy::Default,
-                },
-            },
-        }))
-    )
-    |
-    punct!("!") => { |_| Ty::Never }
-    |
-    delimited!(
-        punct!("("),
-        separated_list!(punct!(","), ty),
-        punct!(")")
-    ) => { Ty::Tup }
-    |
-    path => { |p| Ty::Path(None, p) }
-    |
-    chain!(
-        punct!("<") ~
-        this: map!(ty, Box::new) ~
-        path: opt!(preceded!(
-            tuple!(punct!("as"), space),
-            path
-        )) ~
-        punct!(">") ~
-        punct!("::") ~
-        rest: separated_nonempty_list!(punct!("::"), path_segment),
-        move || {
-            match path {
-                Some(mut path) => {
-                    let pos = path.segments.len();
-                    path.segments.extend(rest);
-                    Ty::Path(Some(QSelf { ty: this, position: pos }), path)
-                }
-                None => {
-                    Ty::Path(Some(QSelf { ty: this, position: 0 }), Path {
-                        global: false,
-                        segments: rest,
-                    })
-                }
-            }
-        }
-    )
-    |
-    preceded!(
-        tuple!(punct!("impl"), space),
-        separated_nonempty_list!(punct!("+"), ty_param_bound)
-    ) => { Ty::ImplTrait }
-    |
-    delimited!(
-        punct!("("),
-        ty,
-        punct!(")")
-    ) => { |inner| Ty::Paren(Box::new(inner)) }
-));
-
-named!(struct_field<&str, Field>, chain!(
-    attrs: many0!(attribute) ~
-    vis: visibility ~
-    ident: word ~
-    punct!(":") ~
-    ty: ty,
-    move || Field {
-        ident: Some(ident),
-        vis: vis,
-        attrs: attrs,
-        ty: ty,
-    }
-));
-
-named!(tuple_field<&str, Field>, chain!(
-    attrs: many0!(attribute) ~
-    vis: visibility ~
-    ty: ty,
-    move || Field {
-        ident: None,
-        vis: vis,
-        attrs: attrs,
-        ty: ty,
-    }
-));
-
-named!(struct_like_body<&str, Vec<Field> >, chain!(
-    punct!("{") ~
-    fields: separated_list!(punct!(","), struct_field) ~
-    punct!(",")? ~
-    punct!("}"),
-    move || fields
-));
-
-named!(tuple_like_body<&str, Vec<Field> >, chain!(
-    punct!("(") ~
-    fields: separated_list!(punct!(","), tuple_field) ~
-    punct!(",")? ~
-    punct!(")"),
-    move || fields
-));
-
-named!(struct_body<&str, (Style, Vec<Field>)>, alt!(
-    struct_like_body => { |fields| (Style::Struct, fields) }
-    |
-    terminated!(tuple_like_body, punct!(";")) => { |fields| (Style::Tuple, fields) }
-    |
-    punct!(";") => { |_| (Style::Unit, Vec::new()) }
-));
-
-named!(variant<&str, Variant>, chain!(
-    attrs: many0!(attribute) ~
-    ident: word ~
-    body: alt!(
-        struct_like_body => { |fields| (Style::Struct, fields) }
-        |
-        tuple_like_body => { |fields| (Style::Tuple, fields) }
-        |
-        epsilon => { |_| (Style::Unit, Vec::new()) }
-    ),
-    move || Variant {
-        ident: ident,
-        attrs: attrs,
-        style: body.0,
-        fields: body.1,
-    }
-));
-
-named!(enum_body<&str, Body>, chain!(
-    punct!("{") ~
-    variants: separated_list!(punct!(","), variant) ~
-    punct!(",")? ~
-    punct!("}"),
-    move || Body::Enum(variants)
-));
-
-named!(lifetime<&str, Lifetime>, preceded!(
-    punct!("'"),
-    map!(word, |ident| Lifetime { ident: ident })
-));
-
-named!(bound_lifetimes<&str, Vec<LifetimeDef> >, opt_vec!(chain!(
-    punct!("for") ~
-    punct!("<") ~
-    lifetimes: separated_list!(punct!(","), lifetime_def) ~
-    punct!(">"),
-    move || lifetimes
-)));
-
-named!(poly_trait_ref<&str, PolyTraitRef>, chain!(
-    bound_lifetimes: bound_lifetimes ~
-    trait_ref: path,
-    move || PolyTraitRef {
-        bound_lifetimes: bound_lifetimes,
-        trait_ref: trait_ref,
-    }
-));
-
-named!(ty_param_bound<&str, TyParamBound>, alt!(
-    tuple!(punct!("?"), punct!("Sized")) => { |_| TyParamBound::MaybeSized }
-    |
-    lifetime => { TyParamBound::Region }
-    |
-    poly_trait_ref => { TyParamBound::Trait }
-));
-
-named!(where_predicate<&str, WherePredicate>, alt!(
-    chain!(
-        ident: lifetime ~
-        punct!(":") ~
-        bounds: separated_nonempty_list!(punct!("+"), lifetime),
-        move || WherePredicate::RegionPredicate(WhereRegionPredicate {
-            lifetime: ident,
-            bounds: bounds,
-        })
-    )
-    |
-    chain!(
-        bound_lifetimes: bound_lifetimes ~
-        bounded_ty: ty ~
-        punct!(":") ~
-        bounds: separated_nonempty_list!(punct!("+"), ty_param_bound),
-        move || WherePredicate::BoundPredicate(WhereBoundPredicate {
-            bound_lifetimes: bound_lifetimes,
-            bounded_ty: bounded_ty,
-            bounds: bounds,
-        })
-    )
-));
-
-named!(lifetime_def<&str, LifetimeDef>, chain!(
-    life: lifetime ~
-    bounds: opt_vec!(preceded!(
-        punct!(":"),
-        separated_nonempty_list!(punct!(","), lifetime)
-    )),
-    move || LifetimeDef {
-        lifetime: life,
-        bounds: bounds,
-    }
-));
-
-named!(ty_param<&str, TyParam>, chain!(
-    ident: word ~
-    bounds: opt_vec!(preceded!(
-        punct!(":"),
-        separated_nonempty_list!(punct!("+"), ty_param_bound)
-    )) ~
-    default: opt!(preceded!(
-        punct!("="),
-        ty
-    )) ~
-    move || TyParam {
-        ident: ident,
-        bounds: bounds,
-        default: default,
-    }
-));
-
-named!(generics<&str, Generics>, chain!(
-    bracketed: alt!(
-        chain!(
-            punct!("<") ~
-            lifetimes: separated_list!(punct!(","), lifetime_def) ~
-            ty_params: opt_vec!(preceded!(
-                cond!(!lifetimes.is_empty(), punct!(",")),
-                separated_nonempty_list!(punct!(","), ty_param)
-            )) ~
-            punct!(">"),
-            move || (lifetimes, ty_params)
-        )
-        |
-        epsilon => { |_| (Vec::new(), Vec::new()) }
-    ) ~
-    where_clause: opt_vec!(chain!(
-        punct!("where") ~
-        space ~
-        predicates: separated_nonempty_list!(punct!(","), where_predicate) ~
-        punct!(",")? ~
-        move || predicates
-    )),
-    move || Generics {
-        lifetimes: bracketed.0,
-        ty_params: bracketed.1,
-        where_clause: where_clause,
-    }
-));
-
-named!(item<&str, Item>, chain!(
-    attrs: many0!(attribute) ~
-    vis: visibility ~
-    which: alt!(tag_s!("struct") | tag_s!("enum")) ~
-    space ~
-    ident: word ~
-    generics: generics ~
-    item: switch!(value!(which),
-        "struct" => map!(struct_body, move |(style, fields)| Item {
-            ident: ident,
-            vis: vis,
-            attrs: attrs,
-            generics: generics,
-            body: Body::Struct(style, fields),
-        })
-        |
-        "enum" => map!(enum_body, move |body| Item {
-            ident: ident,
-            vis: vis,
-            attrs: attrs,
-            generics: generics,
-            body: body,
-        })
-    ) ~
-    space?,
-    move || item
-));
+mod ty;
+pub use ty::{
+    AngleBracketedParameterData,
+    Arg,
+    BareFnTy,
+    FnDecl,
+    FunctionRetTy,
+    MutTy,
+    Mutability,
+    ParenthesizedParameterData,
+    Path,
+    PathParameters,
+    PathSegment,
+    PolyTraitRef,
+    QSelf,
+    Ty,
+    TypeBinding,
+};
 
 pub fn parse(input: &str) -> Item {
-    match item(input) {
-        IResult::Done(rest, ast) => {
+    match item::item(input) {
+        nom::IResult::Done(rest, ast) => {
             if rest.is_empty() {
                 ast
             } else {
                 panic!("more than a single input item: {:?}", rest)
             }
         }
-        IResult::Error(err) => raise(err),
-        IResult::Incomplete(_) => panic!("incomplete input item"),
+        nom::IResult::Error(err) => raise(err),
+        nom::IResult::Incomplete(_) => panic!("incomplete input item"),
     }
 }
 
diff --git a/src/ty.rs b/src/ty.rs
new file mode 100644
index 0000000..0d28e65
--- /dev/null
+++ b/src/ty.rs
@@ -0,0 +1,382 @@
+use super::*;
+
+use common::word;
+use generics::{lifetime, lifetime_def, ty_param_bound, bound_lifetimes};
+use nom::{digit, multispace as space};
+
+use std::str;
+
+#[derive(Debug, Clone, Eq, PartialEq)]
+pub enum Ty {
+    /// A variable-length array (`[T]`)
+    Vec(Box<Ty>),
+    /// A fixed length array (`[T; n]`)
+    FixedLengthVec(Box<Ty>, usize),
+    /// A raw pointer (`*const T` or `*mut T`)
+    Ptr(Box<MutTy>),
+    /// A reference (`&'a T` or `&'a mut T`)
+    Rptr(Option<Lifetime>, Box<MutTy>),
+    /// A bare function (e.g. `fn(usize) -> bool`)
+    BareFn(Box<BareFnTy>),
+    /// The never type (`!`)
+    Never,
+    /// A tuple (`(A, B, C, D, ...)`)
+    Tup(Vec<Ty>),
+    /// A path (`module::module::...::Type`), optionally
+    /// "qualified", e.g. `<Vec<T> as SomeTrait>::SomeType`.
+    ///
+    /// Type parameters are stored in the Path itself
+    Path(Option<QSelf>, Path),
+    /// Something like `A+B`. Note that `B` must always be a path.
+    ObjectSum(Box<Ty>, Vec<TyParamBound>),
+    /// A type like `for<'a> Foo<&'a Bar>`
+    PolyTraitRef(Vec<TyParamBound>),
+    /// An `impl TraitA+TraitB` type.
+    ImplTrait(Vec<TyParamBound>),
+    /// No-op; kept solely so that we can pretty-print faithfully
+    Paren(Box<Ty>),
+    /// TyKind::Infer means the type should be inferred instead of it having been
+    /// specified. This can appear anywhere in a type.
+    Infer,
+}
+
+#[derive(Debug, Clone, Eq, PartialEq)]
+pub struct MutTy {
+    pub ty: Ty,
+    pub mutability: Mutability,
+}
+
+#[derive(Debug, Clone, Eq, PartialEq)]
+pub enum Mutability {
+    Mutable,
+    Immutable,
+}
+
+#[derive(Debug, Clone, Eq, PartialEq)]
+pub struct Path {
+    pub global: bool,
+    pub segments: Vec<PathSegment>,
+}
+
+/// A segment of a path: an identifier, an optional lifetime, and a set of types.
+///
+/// E.g. `std`, `String` or `Box<T>`
+#[derive(Debug, Clone, Eq, PartialEq)]
+pub struct PathSegment {
+    pub ident: Ident,
+    pub parameters: PathParameters,
+}
+
+impl PathSegment {
+    pub fn ident(ident: Ident) -> Self {
+        PathSegment {
+            ident: ident,
+            parameters: PathParameters::none(),
+        }
+    }
+}
+
+/// Parameters of a path segment.
+///
+/// E.g. `<A, B>` as in `Foo<A, B>` or `(A, B)` as in `Foo(A, B)`
+#[derive(Debug, Clone, Eq, PartialEq)]
+pub enum PathParameters {
+    /// The `<'a, A, B, C>` in `foo::bar::baz::<'a, A, B, C>`
+    AngleBracketed(AngleBracketedParameterData),
+    /// The `(A, B)` and `C` in `Foo(A, B) -> C`
+    Parenthesized(ParenthesizedParameterData),
+}
+
+impl PathParameters {
+    pub fn none() -> Self {
+        PathParameters::AngleBracketed(AngleBracketedParameterData::default())
+    }
+}
+
+/// A path like `Foo<'a, T>`
+#[derive(Debug, Clone, Eq, PartialEq, Default)]
+pub struct AngleBracketedParameterData {
+    /// The lifetime parameters for this path segment.
+    pub lifetimes: Vec<Lifetime>,
+    /// The type parameters for this path segment, if present.
+    pub types: Vec<Ty>,
+    /// Bindings (equality constraints) on associated types, if present.
+    ///
+    /// E.g., `Foo<A=Bar>`.
+    pub bindings: Vec<TypeBinding>,
+}
+
+/// Bind a type to an associated type: `A=Foo`.
+#[derive(Debug, Clone, Eq, PartialEq)]
+pub struct TypeBinding {
+    pub ident: Ident,
+    pub ty: Ty,
+}
+
+/// A path like `Foo(A,B) -> C`
+#[derive(Debug, Clone, Eq, PartialEq)]
+pub struct ParenthesizedParameterData {
+    /// `(A, B)`
+    pub inputs: Vec<Ty>,
+    /// `C`
+    pub output: Option<Ty>,
+}
+
+#[derive(Debug, Clone, Eq, PartialEq)]
+pub struct PolyTraitRef {
+    /// The `'a` in `<'a> Foo<&'a T>`
+    pub bound_lifetimes: Vec<LifetimeDef>,
+    /// The `Foo<&'a T>` in `<'a> Foo<&'a T>`
+    pub trait_ref: Path,
+}
+
+/// The explicit Self type in a "qualified path". The actual
+/// path, including the trait and the associated item, is stored
+/// separately. `position` represents the index of the associated
+/// item qualified with this Self type.
+///
+/// ```rust,ignore
+/// <Vec<T> as a::b::Trait>::AssociatedItem
+///  ^~~~~     ~~~~~~~~~~~~~~^
+///  ty        position = 3
+///
+/// <Vec<T>>::AssociatedItem
+///  ^~~~~    ^
+///  ty       position = 0
+/// ```
+#[derive(Debug, Clone, Eq, PartialEq)]
+pub struct QSelf {
+    pub ty: Box<Ty>,
+    pub position: usize
+}
+
+#[derive(Debug, Clone, Eq, PartialEq)]
+pub struct BareFnTy {
+    pub lifetimes: Vec<LifetimeDef>,
+    pub decl: FnDecl
+}
+
+/// Header (not the body) of a function declaration.
+///
+/// E.g. `fn foo(bar: baz)`
+#[derive(Debug, Clone, Eq, PartialEq)]
+pub struct FnDecl {
+    pub inputs: Vec<Arg>,
+    pub output: FunctionRetTy,
+}
+
+/// An argument in a function header.
+///
+/// E.g. `bar: usize` as in `fn foo(bar: usize)`
+#[derive(Debug, Clone, Eq, PartialEq)]
+pub struct Arg {
+    pub pat: Option<Ident>,
+    pub ty: Ty,
+}
+
+#[derive(Debug, Clone, Eq, PartialEq)]
+pub enum FunctionRetTy {
+    /// Return type is not specified.
+    ///
+    /// Functions default to `()` and
+    /// closures default to inference. Span points to where return
+    /// type would be inserted.
+    Default,
+    /// Everything else
+    Ty(Ty),
+}
+
+named!(pub ty<&str, Ty>, alt!(
+    delimited!(
+        punct!("["),
+        ty,
+        punct!("]")
+    ) => { |elem| Ty::Vec(Box::new(elem)) }
+    |
+    chain!(
+        punct!("[") ~
+        elem: ty ~
+        punct!(";") ~
+        space? ~
+        size: map_res!(digit, str::parse),
+        move || Ty::FixedLengthVec(Box::new(elem), size)
+    )
+    |
+    chain!(
+        punct!("*") ~
+        mutability: alt!(
+            punct!("const") => { |_| Mutability::Immutable }
+            |
+            punct!("mut") => { |_| Mutability::Mutable }
+        ) ~
+        target: ty,
+        move || Ty::Ptr(Box::new(MutTy {
+            ty: target,
+            mutability: mutability,
+        }))
+    )
+    |
+    chain!(
+        punct!("&") ~
+        life: lifetime? ~
+        mutability: mutability ~
+        target: ty,
+        move || Ty::Rptr(life, Box::new(MutTy {
+            ty: target,
+            mutability: mutability,
+        }))
+    )
+    |
+    chain!(
+        punct!("fn") ~
+        space ~
+        lifetimes: opt_vec!(delimited!(
+            punct!("<"),
+            separated_list!(punct!(","), lifetime_def),
+            punct!(">")
+        )) ~
+        punct!("(") ~
+        inputs: separated_list!(punct!(","), fn_arg) ~
+        punct!(")") ~
+        output: opt!(preceded!(
+            punct!("->"),
+            ty
+        )),
+        move || Ty::BareFn(Box::new(BareFnTy {
+            lifetimes: lifetimes,
+            decl: FnDecl {
+                inputs: inputs,
+                output: match output {
+                    Some(ty) => FunctionRetTy::Ty(ty),
+                    None => FunctionRetTy::Default,
+                },
+            },
+        }))
+    )
+    |
+    punct!("!") => { |_| Ty::Never }
+    |
+    delimited!(
+        punct!("("),
+        separated_list!(punct!(","), ty),
+        punct!(")")
+    ) => { Ty::Tup }
+    |
+    path => { |p| Ty::Path(None, p) }
+    |
+    chain!(
+        punct!("<") ~
+        this: map!(ty, Box::new) ~
+        path: opt!(preceded!(
+            tuple!(punct!("as"), space),
+            path
+        )) ~
+        punct!(">") ~
+        punct!("::") ~
+        rest: separated_nonempty_list!(punct!("::"), path_segment),
+        move || {
+            match path {
+                Some(mut path) => {
+                    let pos = path.segments.len();
+                    path.segments.extend(rest);
+                    Ty::Path(Some(QSelf { ty: this, position: pos }), path)
+                }
+                None => {
+                    Ty::Path(Some(QSelf { ty: this, position: 0 }), Path {
+                        global: false,
+                        segments: rest,
+                    })
+                }
+            }
+        }
+    )
+    |
+    preceded!(
+        tuple!(punct!("impl"), space),
+        separated_nonempty_list!(punct!("+"), ty_param_bound)
+    ) => { Ty::ImplTrait }
+    |
+    delimited!(
+        punct!("("),
+        ty,
+        punct!(")")
+    ) => { |inner| Ty::Paren(Box::new(inner)) }
+));
+
+named!(mutability<&str, Mutability>, preceded!(
+    opt!(space),
+    alt!(
+        terminated!(tag_s!("mut"), space) => { |_| Mutability::Mutable }
+        |
+        epsilon!() => { |_| Mutability::Immutable }
+    )
+));
+
+named!(path<&str, Path>, chain!(
+    global: punct!("::")? ~
+    segments: separated_nonempty_list!(punct!("::"), path_segment),
+    move || Path {
+        global: global.is_some(),
+        segments: segments,
+    }
+));
+
+named!(path_segment<&str, PathSegment>, alt!(
+    chain!(
+        ident: word ~
+        punct!("<") ~
+        lifetimes: separated_list!(punct!(","), lifetime) ~
+        types: opt_vec!(preceded!(
+            cond!(!lifetimes.is_empty(), punct!(",")),
+            separated_nonempty_list!(
+                punct!(","),
+                terminated!(ty, not!(peek!(punct!("="))))
+            )
+        )) ~
+        bindings: opt_vec!(preceded!(
+            cond!(!lifetimes.is_empty() || !types.is_empty(), punct!(",")),
+            separated_nonempty_list!(punct!(","), type_binding)
+        )) ~
+        punct!(">"),
+        move || PathSegment {
+            ident: ident,
+            parameters: PathParameters::AngleBracketed(
+                AngleBracketedParameterData {
+                    lifetimes: lifetimes,
+                    types: types,
+                    bindings: bindings,
+                }
+            ),
+        }
+    )
+    |
+    map!(word, PathSegment::ident)
+));
+
+named!(type_binding<&str, TypeBinding>, chain!(
+    ident: word ~
+    punct!("=") ~
+    ty: ty,
+    move || TypeBinding {
+        ident: ident,
+        ty: ty,
+    }
+));
+
+named!(pub poly_trait_ref<&str, PolyTraitRef>, chain!(
+    bound_lifetimes: bound_lifetimes ~
+    trait_ref: path,
+    move || PolyTraitRef {
+        bound_lifetimes: bound_lifetimes,
+        trait_ref: trait_ref,
+    }
+));
+
+named!(fn_arg<&str, Arg>, chain!(
+    pat: opt!(terminated!(word, punct!(":"))) ~
+    ty: ty,
+    move || Arg {
+        pat: pat,
+        ty: ty,
+    }
+));