| use super::*; |
| |
| /// An expression. |
| #[derive(Debug, Clone, Eq, PartialEq, Hash)] |
| pub struct Expr { |
| /// Type of the expression. |
| pub node: ExprKind, |
| |
| /// Attributes tagged on the expression. |
| pub attrs: Vec<Attribute>, |
| } |
| |
| impl From<ExprKind> for Expr { |
| fn from(node: ExprKind) -> Expr { |
| Expr { |
| node: node, |
| attrs: Vec::new(), |
| } |
| } |
| } |
| |
| #[derive(Debug, Clone, Eq, PartialEq, Hash)] |
| pub enum ExprKind { |
| /// A `box x` expression. |
| Box(Box<Expr>), |
| |
| /// First expr is the place; second expr is the value. |
| /// |
| /// E.g. 'plae <- val'. |
| InPlace(Box<Expr>, Box<Expr>), |
| |
| /// An array, e.g. `[a, b, c, d]`. |
| Array(Vec<Expr>), |
| |
| /// A function call. |
| /// |
| /// The first field resolves to the function itself, |
| /// and the second field is the list of arguments |
| Call(Box<Expr>, Vec<Expr>), |
| |
| /// A method call (`x.foo::<Bar, Baz>(a, b, c, d)`) |
| /// |
| /// The `Ident` is the identifier for the method name. |
| /// The vector of `Ty`s are the ascripted type parameters for the method |
| /// (within the angle brackets). |
| /// |
| /// The first element of the vector of `Expr`s is the expression that evaluates |
| /// to the object on which the method is being called on (the receiver), |
| /// and the remaining elements are the rest of the arguments. |
| /// |
| /// Thus, `x.foo::<Bar, Baz>(a, b, c, d)` is represented as |
| /// `ExprKind::MethodCall(foo, [Bar, Baz], [x, a, b, c, d])`. |
| MethodCall(Ident, Vec<Ty>, Vec<Expr>), |
| |
| /// A tuple, e.g. `(a, b, c, d)`. |
| Tup(Vec<Expr>), |
| |
| /// A binary operation, e.g. `a + b`, `a * b`. |
| Binary(BinOp, Box<Expr>, Box<Expr>), |
| |
| /// A unary operation, e.g. `!x`, `*x`. |
| Unary(UnOp, Box<Expr>), |
| |
| /// A literal, e.g. `1`, `"foo"`. |
| Lit(Lit), |
| |
| /// A cast, e.g. `foo as f64`. |
| Cast(Box<Expr>, Box<Ty>), |
| |
| /// A type ascription, e.g. `foo: f64`. |
| Type(Box<Expr>, Box<Ty>), |
| |
| /// An `if` block, with an optional else block |
| /// |
| /// E.g., `if expr { block } else { expr }` |
| If(Box<Expr>, Block, Option<Box<Expr>>), |
| |
| /// An `if let` expression with an optional else block |
| /// |
| /// E.g., `if let pat = expr { block } else { expr }` |
| /// |
| /// This is desugared to a `match` expression. |
| IfLet(Box<Pat>, Box<Expr>, Block, Option<Box<Expr>>), |
| |
| /// A while loop, with an optional label |
| /// |
| /// E.g., `'label: while expr { block }` |
| While(Box<Expr>, Block, Option<Ident>), |
| |
| /// A while-let loop, with an optional label. |
| /// |
| /// E.g., `'label: while let pat = expr { block }` |
| /// |
| /// This is desugared to a combination of `loop` and `match` expressions. |
| WhileLet(Box<Pat>, Box<Expr>, Block, Option<Ident>), |
| |
| /// A for loop, with an optional label. |
| /// |
| /// E.g., `'label: for pat in expr { block }` |
| /// |
| /// This is desugared to a combination of `loop` and `match` expressions. |
| ForLoop(Box<Pat>, Box<Expr>, Block, Option<Ident>), |
| |
| /// Conditionless loop with an optional label. |
| /// |
| /// E.g. `'label: loop { block }` |
| Loop(Block, Option<Ident>), |
| |
| /// A `match` block. |
| Match(Box<Expr>, Vec<Arm>), |
| |
| /// A closure (for example, `move |a, b, c| a + b + c`) |
| Closure(CaptureBy, Box<FnDecl>, Box<Expr>), |
| |
| /// A block (`{ ... }` or `unsafe { ... }`) |
| Block(Unsafety, Block), |
| |
| /// An assignment (`a = foo()`) |
| Assign(Box<Expr>, Box<Expr>), |
| |
| /// An assignment with an operator |
| /// |
| /// For example, `a += 1`. |
| AssignOp(BinOp, Box<Expr>, Box<Expr>), |
| |
| /// Access of a named struct field (`obj.foo`) |
| Field(Box<Expr>, Ident), |
| |
| /// Access of an unnamed field of a struct or tuple-struct |
| /// |
| /// For example, `foo.0`. |
| TupField(Box<Expr>, usize), |
| |
| /// An indexing operation (`foo[2]`) |
| Index(Box<Expr>, Box<Expr>), |
| |
| /// A range (`1..2`, `1..`, `..2`, `1...2`, `1...`, `...2`) |
| Range(Option<Box<Expr>>, Option<Box<Expr>>, RangeLimits), |
| |
| /// Variable reference, possibly containing `::` and/or type |
| /// parameters, e.g. foo::bar::<baz>. |
| /// |
| /// Optionally "qualified", |
| /// E.g. `<Vec<T> as SomeTrait>::SomeType`. |
| Path(Option<QSelf>, Path), |
| |
| /// A referencing operation (`&a` or `&mut a`) |
| AddrOf(Mutability, Box<Expr>), |
| |
| /// A `break`, with an optional label to break, and an optional expression |
| Break(Option<Ident>, Option<Box<Expr>>), |
| |
| /// A `continue`, with an optional label |
| Continue(Option<Ident>), |
| |
| /// A `return`, with an optional value to be returned |
| Ret(Option<Box<Expr>>), |
| |
| /// A macro invocation; pre-expansion |
| Mac(Mac), |
| |
| /// A struct literal expression. |
| /// |
| /// For example, `Foo {x: 1, y: 2}`, or |
| /// `Foo {x: 1, .. base}`, where `base` is the `Option<Expr>`. |
| Struct(Path, Vec<FieldValue>, Option<Box<Expr>>), |
| |
| /// An array literal constructed from one repeated element. |
| /// |
| /// For example, `[1; 5]`. The first expression is the element |
| /// to be repeated; the second is the number of times to repeat it. |
| Repeat(Box<Expr>, Box<Expr>), |
| |
| /// No-op: used solely so we can pretty-print faithfully |
| Paren(Box<Expr>), |
| |
| /// `expr?` |
| Try(Box<Expr>), |
| } |
| |
| /// A field-value pair in a struct literal. |
| #[derive(Debug, Clone, Eq, PartialEq, Hash)] |
| pub struct FieldValue { |
| /// Name of the field. |
| pub ident: Ident, |
| |
| /// Value of the field. |
| pub expr: Expr, |
| |
| /// Whether this is a shorthand field, e.g. `Struct { x }` |
| /// instead of `Struct { x: x }`. |
| pub is_shorthand: bool, |
| |
| /// Attributes tagged on the field. |
| pub attrs: Vec<Attribute>, |
| } |
| |
| /// A Block (`{ .. }`). |
| /// |
| /// E.g. `{ .. }` as in `fn foo() { .. }` |
| #[derive(Debug, Clone, Eq, PartialEq, Hash)] |
| pub struct Block { |
| /// Statements in a block |
| pub stmts: Vec<Stmt>, |
| } |
| |
| /// A statement, usually ending in a semicolon. |
| #[derive(Debug, Clone, Eq, PartialEq, Hash)] |
| pub enum Stmt { |
| /// A local (let) binding. |
| Local(Box<Local>), |
| |
| /// An item definition. |
| Item(Box<Item>), |
| |
| /// Expr without trailing semicolon. |
| Expr(Box<Expr>), |
| |
| /// Expression with trailing semicolon; |
| Semi(Box<Expr>), |
| |
| /// Macro invocation. |
| Mac(Box<(Mac, MacStmtStyle, Vec<Attribute>)>), |
| } |
| |
| /// How a macro was invoked. |
| #[derive(Debug, Copy, Clone, Eq, PartialEq, Hash)] |
| pub enum MacStmtStyle { |
| /// The macro statement had a trailing semicolon, e.g. `foo! { ... };` |
| /// `foo!(...);`, `foo![...];` |
| Semicolon, |
| |
| /// The macro statement had braces; e.g. foo! { ... } |
| Braces, |
| |
| /// The macro statement had parentheses or brackets and no semicolon; e.g. |
| /// `foo!(...)`. All of these will end up being converted into macro |
| /// expressions. |
| NoBraces, |
| } |
| |
| /// Local represents a `let` statement, e.g., `let <pat>:<ty> = <expr>;` |
| #[derive(Debug, Clone, Eq, PartialEq, Hash)] |
| pub struct Local { |
| pub pat: Box<Pat>, |
| pub ty: Option<Box<Ty>>, |
| |
| /// Initializer expression to set the value, if any |
| pub init: Option<Box<Expr>>, |
| pub attrs: Vec<Attribute>, |
| } |
| |
| #[derive(Debug, Clone, Eq, PartialEq, Hash)] |
| // Clippy false positive |
| // https://github.com/Manishearth/rust-clippy/issues/1241 |
| #[cfg_attr(feature = "cargo-clippy", allow(enum_variant_names))] |
| pub enum Pat { |
| /// Represents a wildcard pattern (`_`) |
| Wild, |
| |
| /// A `Pat::Ident` may either be a new bound variable (`ref mut binding @ OPT_SUBPATTERN`), |
| /// or a unit struct/variant pattern, or a const pattern (in the last two cases the third |
| /// field must be `None`). Disambiguation cannot be done with parser alone, so it happens |
| /// during name resolution. |
| Ident(BindingMode, Ident, Option<Box<Pat>>), |
| |
| /// A struct or struct variant pattern, e.g. `Variant {x, y, ..}`. |
| /// The `bool` is `true` in the presence of a `..`. |
| Struct(Path, Vec<FieldPat>, bool), |
| |
| /// A tuple struct/variant pattern `Variant(x, y, .., z)`. |
| /// If the `..` pattern fragment is present, then `Option<usize>` denotes its position. |
| /// 0 <= position <= subpats.len() |
| TupleStruct(Path, Vec<Pat>, Option<usize>), |
| |
| /// A possibly qualified path pattern. |
| /// Unquailfied path patterns `A::B::C` can legally refer to variants, structs, constants |
| /// or associated constants. Quailfied path patterns `<A>::B::C`/`<A as Trait>::B::C` can |
| /// only legally refer to associated constants. |
| Path(Option<QSelf>, Path), |
| |
| /// A tuple pattern `(a, b)`. |
| /// If the `..` pattern fragment is present, then `Option<usize>` denotes its position. |
| /// 0 <= position <= subpats.len() |
| Tuple(Vec<Pat>, Option<usize>), |
| /// A `box` pattern |
| Box(Box<Pat>), |
| /// A reference pattern, e.g. `&mut (a, b)` |
| Ref(Box<Pat>, Mutability), |
| /// A literal |
| Lit(Box<Expr>), |
| /// A range pattern, e.g. `1...2` |
| Range(Box<Expr>, Box<Expr>), |
| /// `[a, b, ..i, y, z]` is represented as: |
| /// `Pat::Slice(box [a, b], Some(i), box [y, z])` |
| Slice(Vec<Pat>, Option<Box<Pat>>, Vec<Pat>), |
| /// A macro pattern; pre-expansion |
| Mac(Mac), |
| } |
| |
| /// An arm of a 'match'. |
| /// |
| /// E.g. `0...10 => { println!("match!") }` as in |
| /// |
| /// ```rust,ignore |
| /// match n { |
| /// 0...10 => { println!("match!") }, |
| /// // .. |
| /// } |
| /// ``` |
| #[derive(Debug, Clone, Eq, PartialEq, Hash)] |
| pub struct Arm { |
| pub attrs: Vec<Attribute>, |
| pub pats: Vec<Pat>, |
| pub guard: Option<Box<Expr>>, |
| pub body: Box<Expr>, |
| } |
| |
| /// A capture clause |
| #[derive(Debug, Copy, Clone, Eq, PartialEq, Hash)] |
| pub enum CaptureBy { |
| Value, |
| Ref, |
| } |
| |
| /// Limit types of a range (inclusive or exclusive) |
| #[derive(Debug, Copy, Clone, Eq, PartialEq, Hash)] |
| pub enum RangeLimits { |
| /// Inclusive at the beginning, exclusive at the end |
| HalfOpen, |
| /// Inclusive at the beginning and end |
| Closed, |
| } |
| |
| /// A single field in a struct pattern |
| /// |
| /// Patterns like the fields of Foo `{ x, ref y, ref mut z }` |
| /// are treated the same as `x: x, y: ref y, z: ref mut z`, |
| /// except `is_shorthand` is true |
| #[derive(Debug, Clone, Eq, PartialEq, Hash)] |
| pub struct FieldPat { |
| /// The identifier for the field |
| pub ident: Ident, |
| /// The pattern the field is destructured to |
| pub pat: Box<Pat>, |
| pub is_shorthand: bool, |
| pub attrs: Vec<Attribute>, |
| } |
| |
| #[derive(Debug, Copy, Clone, Eq, PartialEq, Hash)] |
| pub enum BindingMode { |
| ByRef(Mutability), |
| ByValue(Mutability), |
| } |
| |
| #[cfg(feature = "parsing")] |
| pub mod parsing { |
| use super::*; |
| use {BinOp, Delimited, DelimToken, FnArg, FnDecl, FunctionRetTy, Ident, Lifetime, Mac, |
| TokenTree, Ty, UnOp, Unsafety}; |
| use attr::parsing::outer_attr; |
| use generics::parsing::lifetime; |
| use ident::parsing::{ident, wordlike}; |
| use item::parsing::item; |
| use lit::parsing::{digits, lit}; |
| use mac::parsing::{mac, token_trees}; |
| use synom::IResult::{self, Error}; |
| use op::parsing::{assign_op, binop, unop}; |
| use ty::parsing::{mutability, path, qpath, ty, unsafety}; |
| |
| // Struct literals are ambiguous in certain positions |
| // https://github.com/rust-lang/rfcs/pull/92 |
| macro_rules! named_ambiguous_expr { |
| ($name:ident -> $o:ty, $allow_struct:ident, $submac:ident!( $($args:tt)* )) => { |
| fn $name(i: &str, $allow_struct: bool) -> $crate::synom::IResult<&str, $o> { |
| $submac!(i, $($args)*) |
| } |
| }; |
| } |
| |
| macro_rules! ambiguous_expr { |
| ($i:expr, $allow_struct:ident) => { |
| ambiguous_expr($i, $allow_struct, true) |
| }; |
| } |
| |
| named!(pub expr -> Expr, ambiguous_expr!(true)); |
| |
| named!(expr_no_struct -> Expr, ambiguous_expr!(false)); |
| |
| #[cfg_attr(feature = "cargo-clippy", allow(cyclomatic_complexity))] |
| fn ambiguous_expr(i: &str, allow_struct: bool, allow_block: bool) -> IResult<&str, Expr> { |
| do_parse!( |
| i, |
| mut e: alt!( |
| expr_lit // must be before expr_struct |
| | |
| cond_reduce!(allow_struct, expr_struct) // must be before expr_path |
| | |
| expr_paren // must be before expr_tup |
| | |
| expr_mac // must be before expr_path |
| | |
| call!(expr_break, allow_struct) // must be before expr_path |
| | |
| expr_continue // must be before expr_path |
| | |
| call!(expr_ret, allow_struct) // must be before expr_path |
| | |
| call!(expr_box, allow_struct) |
| | |
| expr_in_place |
| | |
| expr_array |
| | |
| expr_tup |
| | |
| call!(expr_unary, allow_struct) |
| | |
| expr_if |
| | |
| expr_while |
| | |
| expr_for_loop |
| | |
| expr_loop |
| | |
| expr_match |
| | |
| call!(expr_closure, allow_struct) |
| | |
| cond_reduce!(allow_block, expr_block) |
| | |
| call!(expr_range, allow_struct) |
| | |
| expr_path |
| | |
| call!(expr_addr_of, allow_struct) |
| | |
| expr_repeat |
| ) >> |
| many0!(alt!( |
| tap!(args: and_call => { |
| e = ExprKind::Call(Box::new(e.into()), args); |
| }) |
| | |
| tap!(more: and_method_call => { |
| let (method, ascript, mut args) = more; |
| args.insert(0, e.into()); |
| e = ExprKind::MethodCall(method, ascript, args); |
| }) |
| | |
| tap!(more: call!(and_binary, allow_struct) => { |
| let (op, other) = more; |
| e = ExprKind::Binary(op, Box::new(e.into()), Box::new(other)); |
| }) |
| | |
| tap!(ty: and_cast => { |
| e = ExprKind::Cast(Box::new(e.into()), Box::new(ty)); |
| }) |
| | |
| tap!(ty: and_ascription => { |
| e = ExprKind::Type(Box::new(e.into()), Box::new(ty)); |
| }) |
| | |
| tap!(v: call!(and_assign, allow_struct) => { |
| e = ExprKind::Assign(Box::new(e.into()), Box::new(v)); |
| }) |
| | |
| tap!(more: call!(and_assign_op, allow_struct) => { |
| let (op, v) = more; |
| e = ExprKind::AssignOp(op, Box::new(e.into()), Box::new(v)); |
| }) |
| | |
| tap!(field: and_field => { |
| e = ExprKind::Field(Box::new(e.into()), field); |
| }) |
| | |
| tap!(field: and_tup_field => { |
| e = ExprKind::TupField(Box::new(e.into()), field as usize); |
| }) |
| | |
| tap!(i: and_index => { |
| e = ExprKind::Index(Box::new(e.into()), Box::new(i)); |
| }) |
| | |
| tap!(more: call!(and_range, allow_struct) => { |
| let (limits, hi) = more; |
| e = ExprKind::Range(Some(Box::new(e.into())), hi.map(Box::new), limits); |
| }) |
| | |
| tap!(_try: punct!("?") => { |
| e = ExprKind::Try(Box::new(e.into())); |
| }) |
| )) >> |
| (e.into()) |
| ) |
| } |
| |
| named!(expr_mac -> ExprKind, map!(mac, ExprKind::Mac)); |
| |
| named!(expr_paren -> ExprKind, do_parse!( |
| punct!("(") >> |
| e: expr >> |
| punct!(")") >> |
| (ExprKind::Paren(Box::new(e))) |
| )); |
| |
| named_ambiguous_expr!(expr_box -> ExprKind, allow_struct, do_parse!( |
| keyword!("box") >> |
| inner: ambiguous_expr!(allow_struct) >> |
| (ExprKind::Box(Box::new(inner))) |
| )); |
| |
| named!(expr_in_place -> ExprKind, do_parse!( |
| keyword!("in") >> |
| place: expr_no_struct >> |
| punct!("{") >> |
| value: within_block >> |
| punct!("}") >> |
| (ExprKind::InPlace( |
| Box::new(place), |
| Box::new(ExprKind::Block(Unsafety::Normal, Block { |
| stmts: value, |
| }).into()), |
| )) |
| )); |
| |
| named!(expr_array -> ExprKind, do_parse!( |
| punct!("[") >> |
| elems: terminated_list!(punct!(","), expr) >> |
| punct!("]") >> |
| (ExprKind::Array(elems)) |
| )); |
| |
| named!(and_call -> Vec<Expr>, do_parse!( |
| punct!("(") >> |
| args: terminated_list!(punct!(","), expr) >> |
| punct!(")") >> |
| (args) |
| )); |
| |
| named!(and_method_call -> (Ident, Vec<Ty>, Vec<Expr>), do_parse!( |
| punct!(".") >> |
| method: ident >> |
| ascript: opt_vec!(preceded!( |
| punct!("::"), |
| delimited!( |
| punct!("<"), |
| terminated_list!(punct!(","), ty), |
| punct!(">") |
| ) |
| )) >> |
| punct!("(") >> |
| args: terminated_list!(punct!(","), expr) >> |
| punct!(")") >> |
| (method, ascript, args) |
| )); |
| |
| named!(expr_tup -> ExprKind, do_parse!( |
| punct!("(") >> |
| elems: terminated_list!(punct!(","), expr) >> |
| punct!(")") >> |
| (ExprKind::Tup(elems)) |
| )); |
| |
| named_ambiguous_expr!(and_binary -> (BinOp, Expr), allow_struct, tuple!( |
| binop, |
| ambiguous_expr!(allow_struct) |
| )); |
| |
| named_ambiguous_expr!(expr_unary -> ExprKind, allow_struct, do_parse!( |
| operator: unop >> |
| operand: ambiguous_expr!(allow_struct) >> |
| (ExprKind::Unary(operator, Box::new(operand))) |
| )); |
| |
| named!(expr_lit -> ExprKind, map!(lit, ExprKind::Lit)); |
| |
| named!(and_cast -> Ty, do_parse!( |
| keyword!("as") >> |
| ty: ty >> |
| (ty) |
| )); |
| |
| named!(and_ascription -> Ty, preceded!(punct!(":"), ty)); |
| |
| enum Cond { |
| Let(Pat, Expr), |
| Expr(Expr), |
| } |
| |
| named!(cond -> Cond, alt!( |
| do_parse!( |
| keyword!("let") >> |
| pat: pat >> |
| punct!("=") >> |
| value: expr_no_struct >> |
| (Cond::Let(pat, value)) |
| ) |
| | |
| map!(expr_no_struct, Cond::Expr) |
| )); |
| |
| named!(expr_if -> ExprKind, do_parse!( |
| keyword!("if") >> |
| cond: cond >> |
| punct!("{") >> |
| then_block: within_block >> |
| punct!("}") >> |
| else_block: option!(preceded!( |
| keyword!("else"), |
| alt!( |
| expr_if |
| | |
| do_parse!( |
| punct!("{") >> |
| else_block: within_block >> |
| punct!("}") >> |
| (ExprKind::Block(Unsafety::Normal, Block { |
| stmts: else_block, |
| }).into()) |
| ) |
| ) |
| )) >> |
| (match cond { |
| Cond::Let(pat, expr) => ExprKind::IfLet( |
| Box::new(pat), |
| Box::new(expr), |
| Block { |
| stmts: then_block, |
| }, |
| else_block.map(|els| Box::new(els.into())), |
| ), |
| Cond::Expr(cond) => ExprKind::If( |
| Box::new(cond), |
| Block { |
| stmts: then_block, |
| }, |
| else_block.map(|els| Box::new(els.into())), |
| ), |
| }) |
| )); |
| |
| named!(expr_for_loop -> ExprKind, do_parse!( |
| lbl: option!(terminated!(label, punct!(":"))) >> |
| keyword!("for") >> |
| pat: pat >> |
| keyword!("in") >> |
| expr: expr_no_struct >> |
| loop_block: block >> |
| (ExprKind::ForLoop(Box::new(pat), Box::new(expr), loop_block, lbl)) |
| )); |
| |
| named!(expr_loop -> ExprKind, do_parse!( |
| lbl: option!(terminated!(label, punct!(":"))) >> |
| keyword!("loop") >> |
| loop_block: block >> |
| (ExprKind::Loop(loop_block, lbl)) |
| )); |
| |
| named!(expr_match -> ExprKind, do_parse!( |
| keyword!("match") >> |
| obj: expr_no_struct >> |
| punct!("{") >> |
| mut arms: many0!(do_parse!( |
| arm: match_arm >> |
| cond!(arm_requires_comma(&arm), punct!(",")) >> |
| cond!(!arm_requires_comma(&arm), option!(punct!(","))) >> |
| (arm) |
| )) >> |
| last_arm: option!(match_arm) >> |
| punct!("}") >> |
| (ExprKind::Match(Box::new(obj), { |
| arms.extend(last_arm); |
| arms |
| })) |
| )); |
| |
| fn arm_requires_comma(arm: &Arm) -> bool { |
| if let ExprKind::Block(Unsafety::Normal, _) = arm.body.node { |
| false |
| } else { |
| true |
| } |
| } |
| |
| named!(match_arm -> Arm, do_parse!( |
| attrs: many0!(outer_attr) >> |
| pats: separated_nonempty_list!(punct!("|"), pat) >> |
| guard: option!(preceded!(keyword!("if"), expr)) >> |
| punct!("=>") >> |
| body: alt!( |
| map!(block, |blk| ExprKind::Block(Unsafety::Normal, blk).into()) |
| | |
| expr |
| ) >> |
| (Arm { |
| attrs: attrs, |
| pats: pats, |
| guard: guard.map(Box::new), |
| body: Box::new(body), |
| }) |
| )); |
| |
| named_ambiguous_expr!(expr_closure -> ExprKind, allow_struct, do_parse!( |
| capture: capture_by >> |
| punct!("|") >> |
| inputs: terminated_list!(punct!(","), closure_arg) >> |
| punct!("|") >> |
| ret_and_body: alt!( |
| do_parse!( |
| punct!("->") >> |
| ty: ty >> |
| body: block >> |
| (FunctionRetTy::Ty(ty), ExprKind::Block(Unsafety::Normal, body).into()) |
| ) |
| | |
| map!(ambiguous_expr!(allow_struct), |e| (FunctionRetTy::Default, e)) |
| ) >> |
| (ExprKind::Closure( |
| capture, |
| Box::new(FnDecl { |
| inputs: inputs, |
| output: ret_and_body.0, |
| variadic: false, |
| }), |
| Box::new(ret_and_body.1), |
| )) |
| )); |
| |
| named!(closure_arg -> FnArg, do_parse!( |
| pat: pat >> |
| ty: option!(preceded!(punct!(":"), ty)) >> |
| (FnArg::Captured(pat, ty.unwrap_or(Ty::Infer))) |
| )); |
| |
| named!(expr_while -> ExprKind, do_parse!( |
| lbl: option!(terminated!(label, punct!(":"))) >> |
| keyword!("while") >> |
| cond: cond >> |
| while_block: block >> |
| (match cond { |
| Cond::Let(pat, expr) => ExprKind::WhileLet( |
| Box::new(pat), |
| Box::new(expr), |
| while_block, |
| lbl, |
| ), |
| Cond::Expr(cond) => ExprKind::While( |
| Box::new(cond), |
| while_block, |
| lbl, |
| ), |
| }) |
| )); |
| |
| named!(expr_continue -> ExprKind, do_parse!( |
| keyword!("continue") >> |
| lbl: option!(label) >> |
| (ExprKind::Continue(lbl)) |
| )); |
| |
| named_ambiguous_expr!(expr_break -> ExprKind, allow_struct, do_parse!( |
| keyword!("break") >> |
| lbl: option!(label) >> |
| val: option!(call!(ambiguous_expr, allow_struct, false)) >> |
| (ExprKind::Break(lbl, val.map(Box::new))) |
| )); |
| |
| named_ambiguous_expr!(expr_ret -> ExprKind, allow_struct, do_parse!( |
| keyword!("return") >> |
| ret_value: option!(ambiguous_expr!(allow_struct)) >> |
| (ExprKind::Ret(ret_value.map(Box::new))) |
| )); |
| |
| named!(expr_struct -> ExprKind, do_parse!( |
| path: path >> |
| punct!("{") >> |
| fields: separated_list!(punct!(","), field_value) >> |
| base: option!(do_parse!( |
| cond!(!fields.is_empty(), punct!(",")) >> |
| punct!("..") >> |
| base: expr >> |
| (base) |
| )) >> |
| cond!(!fields.is_empty() && base.is_none(), option!(punct!(","))) >> |
| punct!("}") >> |
| (ExprKind::Struct(path, fields, base.map(Box::new))) |
| )); |
| |
| named!(field_value -> FieldValue, alt!( |
| do_parse!( |
| name: wordlike >> |
| punct!(":") >> |
| value: expr >> |
| (FieldValue { |
| ident: name, |
| expr: value, |
| is_shorthand: false, |
| attrs: Vec::new(), |
| }) |
| ) |
| | |
| map!(ident, |name: Ident| FieldValue { |
| ident: name.clone(), |
| expr: ExprKind::Path(None, name.into()).into(), |
| is_shorthand: true, |
| attrs: Vec::new(), |
| }) |
| )); |
| |
| named!(expr_repeat -> ExprKind, do_parse!( |
| punct!("[") >> |
| value: expr >> |
| punct!(";") >> |
| times: expr >> |
| punct!("]") >> |
| (ExprKind::Repeat(Box::new(value), Box::new(times))) |
| )); |
| |
| named!(expr_block -> ExprKind, do_parse!( |
| rules: unsafety >> |
| b: block >> |
| (ExprKind::Block(rules, Block { |
| stmts: b.stmts, |
| })) |
| )); |
| |
| named_ambiguous_expr!(expr_range -> ExprKind, allow_struct, do_parse!( |
| limits: range_limits >> |
| hi: option!(ambiguous_expr!(allow_struct)) >> |
| (ExprKind::Range(None, hi.map(Box::new), limits)) |
| )); |
| |
| named!(range_limits -> RangeLimits, alt!( |
| punct!("...") => { |_| RangeLimits::Closed } |
| | |
| punct!("..") => { |_| RangeLimits::HalfOpen } |
| )); |
| |
| named!(expr_path -> ExprKind, map!(qpath, |(qself, path)| ExprKind::Path(qself, path))); |
| |
| named_ambiguous_expr!(expr_addr_of -> ExprKind, allow_struct, do_parse!( |
| punct!("&") >> |
| mutability: mutability >> |
| expr: ambiguous_expr!(allow_struct) >> |
| (ExprKind::AddrOf(mutability, Box::new(expr))) |
| )); |
| |
| named_ambiguous_expr!(and_assign -> Expr, allow_struct, preceded!( |
| punct!("="), |
| ambiguous_expr!(allow_struct) |
| )); |
| |
| named_ambiguous_expr!(and_assign_op -> (BinOp, Expr), allow_struct, tuple!( |
| assign_op, |
| ambiguous_expr!(allow_struct) |
| )); |
| |
| named!(and_field -> Ident, preceded!(punct!("."), ident)); |
| |
| named!(and_tup_field -> u64, preceded!(punct!("."), digits)); |
| |
| named!(and_index -> Expr, delimited!(punct!("["), expr, punct!("]"))); |
| |
| named_ambiguous_expr!(and_range -> (RangeLimits, Option<Expr>), allow_struct, tuple!( |
| range_limits, |
| option!(call!(ambiguous_expr, allow_struct, false)) |
| )); |
| |
| named!(pub block -> Block, do_parse!( |
| punct!("{") >> |
| stmts: within_block >> |
| punct!("}") >> |
| (Block { |
| stmts: stmts, |
| }) |
| )); |
| |
| named!(pub within_block -> Vec<Stmt>, do_parse!( |
| many0!(punct!(";")) >> |
| mut standalone: many0!(terminated!(stmt, many0!(punct!(";")))) >> |
| last: option!(expr) >> |
| (match last { |
| None => standalone, |
| Some(last) => { |
| standalone.push(Stmt::Expr(Box::new(last))); |
| standalone |
| } |
| }) |
| )); |
| |
| named!(pub stmt -> Stmt, alt!( |
| stmt_mac |
| | |
| stmt_local |
| | |
| stmt_item |
| | |
| stmt_expr |
| )); |
| |
| named!(stmt_mac -> Stmt, do_parse!( |
| attrs: many0!(outer_attr) >> |
| what: path >> |
| punct!("!") >> |
| // Only parse braces here; paren and bracket will get parsed as |
| // expression statements |
| punct!("{") >> |
| tts: token_trees >> |
| punct!("}") >> |
| semi: option!(punct!(";")) >> |
| (Stmt::Mac(Box::new(( |
| Mac { |
| path: what, |
| tts: vec![TokenTree::Delimited(Delimited { |
| delim: DelimToken::Brace, |
| tts: tts, |
| })], |
| }, |
| if semi.is_some() { |
| MacStmtStyle::Semicolon |
| } else { |
| MacStmtStyle::Braces |
| }, |
| attrs, |
| )))) |
| )); |
| |
| named!(stmt_local -> Stmt, do_parse!( |
| attrs: many0!(outer_attr) >> |
| keyword!("let") >> |
| pat: pat >> |
| ty: option!(preceded!(punct!(":"), ty)) >> |
| init: option!(preceded!(punct!("="), expr)) >> |
| punct!(";") >> |
| (Stmt::Local(Box::new(Local { |
| pat: Box::new(pat), |
| ty: ty.map(Box::new), |
| init: init.map(Box::new), |
| attrs: attrs, |
| }))) |
| )); |
| |
| named!(stmt_item -> Stmt, map!(item, |i| Stmt::Item(Box::new(i)))); |
| |
| fn requires_semi(e: &Expr) -> bool { |
| match e.node { |
| ExprKind::If(_, _, _) | |
| ExprKind::IfLet(_, _, _, _) | |
| ExprKind::While(_, _, _) | |
| ExprKind::WhileLet(_, _, _, _) | |
| ExprKind::ForLoop(_, _, _, _) | |
| ExprKind::Loop(_, _) | |
| ExprKind::Match(_, _) | |
| ExprKind::Block(_, _) => false, |
| |
| _ => true, |
| } |
| } |
| |
| named!(stmt_expr -> Stmt, do_parse!( |
| attrs: many0!(outer_attr) >> |
| mut e: expr >> |
| semi: option!(punct!(";")) >> |
| ({ |
| e.attrs = attrs; |
| if semi.is_some() { |
| Stmt::Semi(Box::new(e)) |
| } else if requires_semi(&e) { |
| return Error; |
| } else { |
| Stmt::Expr(Box::new(e)) |
| } |
| }) |
| )); |
| |
| named!(pub pat -> Pat, alt!( |
| pat_wild // must be before pat_ident |
| | |
| pat_box // must be before pat_ident |
| | |
| pat_range // must be before pat_lit |
| | |
| pat_tuple_struct // must be before pat_ident |
| | |
| pat_struct // must be before pat_ident |
| | |
| pat_mac // must be before pat_ident |
| | |
| pat_lit // must be before pat_ident |
| | |
| pat_ident // must be before pat_path |
| | |
| pat_path |
| | |
| pat_tuple |
| | |
| pat_ref |
| | |
| pat_slice |
| )); |
| |
| named!(pat_mac -> Pat, map!(mac, Pat::Mac)); |
| |
| named!(pat_wild -> Pat, map!(keyword!("_"), |_| Pat::Wild)); |
| |
| named!(pat_box -> Pat, do_parse!( |
| keyword!("box") >> |
| pat: pat >> |
| (Pat::Box(Box::new(pat))) |
| )); |
| |
| named!(pat_ident -> Pat, do_parse!( |
| mode: option!(keyword!("ref")) >> |
| mutability: mutability >> |
| name: alt!( |
| ident |
| | |
| keyword!("self") => { Into::into } |
| ) >> |
| not!(punct!("<")) >> |
| not!(punct!("::")) >> |
| subpat: option!(preceded!(punct!("@"), pat)) >> |
| (Pat::Ident( |
| if mode.is_some() { |
| BindingMode::ByRef(mutability) |
| } else { |
| BindingMode::ByValue(mutability) |
| }, |
| name, |
| subpat.map(Box::new), |
| )) |
| )); |
| |
| named!(pat_tuple_struct -> Pat, do_parse!( |
| path: path >> |
| tuple: pat_tuple_helper >> |
| (Pat::TupleStruct(path, tuple.0, tuple.1)) |
| )); |
| |
| named!(pat_struct -> Pat, do_parse!( |
| path: path >> |
| punct!("{") >> |
| fields: separated_list!(punct!(","), field_pat) >> |
| more: option!(preceded!( |
| cond!(!fields.is_empty(), punct!(",")), |
| punct!("..") |
| )) >> |
| cond!(!fields.is_empty() && more.is_none(), option!(punct!(","))) >> |
| punct!("}") >> |
| (Pat::Struct(path, fields, more.is_some())) |
| )); |
| |
| named!(field_pat -> FieldPat, alt!( |
| do_parse!( |
| ident: wordlike >> |
| punct!(":") >> |
| pat: pat >> |
| (FieldPat { |
| ident: ident, |
| pat: Box::new(pat), |
| is_shorthand: false, |
| attrs: Vec::new(), |
| }) |
| ) |
| | |
| do_parse!( |
| boxed: option!(keyword!("box")) >> |
| mode: option!(keyword!("ref")) >> |
| mutability: mutability >> |
| ident: ident >> |
| ({ |
| let mut pat = Pat::Ident( |
| if mode.is_some() { |
| BindingMode::ByRef(mutability) |
| } else { |
| BindingMode::ByValue(mutability) |
| }, |
| ident.clone(), |
| None, |
| ); |
| if boxed.is_some() { |
| pat = Pat::Box(Box::new(pat)); |
| } |
| FieldPat { |
| ident: ident, |
| pat: Box::new(pat), |
| is_shorthand: true, |
| attrs: Vec::new(), |
| } |
| }) |
| ) |
| )); |
| |
| named!(pat_path -> Pat, map!(qpath, |(qself, path)| Pat::Path(qself, path))); |
| |
| named!(pat_tuple -> Pat, map!( |
| pat_tuple_helper, |
| |(pats, dotdot)| Pat::Tuple(pats, dotdot) |
| )); |
| |
| named!(pat_tuple_helper -> (Vec<Pat>, Option<usize>), do_parse!( |
| punct!("(") >> |
| mut elems: separated_list!(punct!(","), pat) >> |
| dotdot: option!(do_parse!( |
| cond!(!elems.is_empty(), punct!(",")) >> |
| punct!("..") >> |
| rest: many0!(preceded!(punct!(","), pat)) >> |
| cond!(!rest.is_empty(), option!(punct!(","))) >> |
| (rest) |
| )) >> |
| cond!(!elems.is_empty() && dotdot.is_none(), option!(punct!(","))) >> |
| punct!(")") >> |
| (match dotdot { |
| Some(rest) => { |
| let pos = elems.len(); |
| elems.extend(rest); |
| (elems, Some(pos)) |
| } |
| None => (elems, None), |
| }) |
| )); |
| |
| named!(pat_ref -> Pat, do_parse!( |
| punct!("&") >> |
| mutability: mutability >> |
| pat: pat >> |
| (Pat::Ref(Box::new(pat), mutability)) |
| )); |
| |
| named!(pat_lit -> Pat, do_parse!( |
| lit: pat_lit_expr >> |
| (if let ExprKind::Path(_, _) = lit.node { |
| return IResult::Error; // these need to be parsed by pat_path |
| } else { |
| Pat::Lit(Box::new(lit)) |
| }) |
| )); |
| |
| named!(pat_range -> Pat, do_parse!( |
| lo: pat_lit_expr >> |
| punct!("...") >> |
| hi: pat_lit_expr >> |
| (Pat::Range(Box::new(lo), Box::new(hi))) |
| )); |
| |
| named!(pat_lit_expr -> Expr, do_parse!( |
| neg: option!(punct!("-")) >> |
| v: alt!( |
| lit => { ExprKind::Lit } |
| | |
| path => { |p| ExprKind::Path(None, p) } |
| ) >> |
| (if neg.is_some() { |
| ExprKind::Unary(UnOp::Neg, Box::new(v.into())).into() |
| } else { |
| v.into() |
| }) |
| )); |
| |
| named!(pat_slice -> Pat, do_parse!( |
| punct!("[") >> |
| mut before: separated_list!(punct!(","), pat) >> |
| after: option!(do_parse!( |
| comma_before_dots: option!(cond_reduce!(!before.is_empty(), punct!(","))) >> |
| punct!("..") >> |
| after: many0!(preceded!(punct!(","), pat)) >> |
| cond!(!after.is_empty(), option!(punct!(","))) >> |
| (comma_before_dots.is_some(), after) |
| )) >> |
| cond!(after.is_none(), option!(punct!(","))) >> |
| punct!("]") >> |
| (match after { |
| None => Pat::Slice(before, None, Vec::new()), |
| Some((true, after)) => { |
| if before.is_empty() { |
| return IResult::Error; |
| } |
| Pat::Slice(before, Some(Box::new(Pat::Wild)), after) |
| } |
| Some((false, after)) => { |
| let rest = before.pop().unwrap_or(Pat::Wild); |
| Pat::Slice(before, Some(Box::new(rest)), after) |
| } |
| }) |
| )); |
| |
| named!(capture_by -> CaptureBy, alt!( |
| keyword!("move") => { |_| CaptureBy::Value } |
| | |
| epsilon!() => { |_| CaptureBy::Ref } |
| )); |
| |
| named!(label -> Ident, map!(lifetime, |lt: Lifetime| lt.ident)); |
| } |
| |
| #[cfg(feature = "printing")] |
| mod printing { |
| use super::*; |
| use {FnArg, FunctionRetTy, Mutability, Ty, Unsafety}; |
| use attr::FilterAttrs; |
| use quote::{Tokens, ToTokens}; |
| |
| impl ToTokens for Expr { |
| fn to_tokens(&self, tokens: &mut Tokens) { |
| tokens.append_all(self.attrs.outer()); |
| match self.node { |
| ExprKind::Box(ref inner) => { |
| tokens.append("box"); |
| inner.to_tokens(tokens); |
| } |
| ExprKind::InPlace(ref place, ref value) => { |
| tokens.append("in"); |
| place.to_tokens(tokens); |
| value.to_tokens(tokens); |
| } |
| ExprKind::Array(ref tys) => { |
| tokens.append("["); |
| tokens.append_separated(tys, ","); |
| tokens.append("]"); |
| } |
| ExprKind::Call(ref func, ref args) => { |
| func.to_tokens(tokens); |
| tokens.append("("); |
| tokens.append_separated(args, ","); |
| tokens.append(")"); |
| } |
| ExprKind::MethodCall(ref ident, ref ascript, ref args) => { |
| args[0].to_tokens(tokens); |
| tokens.append("."); |
| ident.to_tokens(tokens); |
| if !ascript.is_empty() { |
| tokens.append("::"); |
| tokens.append("<"); |
| tokens.append_separated(ascript, ","); |
| tokens.append(">"); |
| } |
| tokens.append("("); |
| tokens.append_separated(&args[1..], ","); |
| tokens.append(")"); |
| } |
| ExprKind::Tup(ref fields) => { |
| tokens.append("("); |
| tokens.append_separated(fields, ","); |
| if fields.len() == 1 { |
| tokens.append(","); |
| } |
| tokens.append(")"); |
| } |
| ExprKind::Binary(op, ref left, ref right) => { |
| left.to_tokens(tokens); |
| op.to_tokens(tokens); |
| right.to_tokens(tokens); |
| } |
| ExprKind::Unary(op, ref expr) => { |
| op.to_tokens(tokens); |
| expr.to_tokens(tokens); |
| } |
| ExprKind::Lit(ref lit) => lit.to_tokens(tokens), |
| ExprKind::Cast(ref expr, ref ty) => { |
| expr.to_tokens(tokens); |
| tokens.append("as"); |
| ty.to_tokens(tokens); |
| } |
| ExprKind::Type(ref expr, ref ty) => { |
| expr.to_tokens(tokens); |
| tokens.append(":"); |
| ty.to_tokens(tokens); |
| } |
| ExprKind::If(ref cond, ref then_block, ref else_block) => { |
| tokens.append("if"); |
| cond.to_tokens(tokens); |
| then_block.to_tokens(tokens); |
| if let Some(ref else_block) = *else_block { |
| tokens.append("else"); |
| else_block.to_tokens(tokens); |
| } |
| } |
| ExprKind::IfLet(ref pat, ref expr, ref then_block, ref else_block) => { |
| tokens.append("if"); |
| tokens.append("let"); |
| pat.to_tokens(tokens); |
| tokens.append("="); |
| expr.to_tokens(tokens); |
| then_block.to_tokens(tokens); |
| if let Some(ref else_block) = *else_block { |
| tokens.append("else"); |
| else_block.to_tokens(tokens); |
| } |
| } |
| ExprKind::While(ref cond, ref body, ref label) => { |
| if let Some(ref label) = *label { |
| label.to_tokens(tokens); |
| tokens.append(":"); |
| } |
| tokens.append("while"); |
| cond.to_tokens(tokens); |
| body.to_tokens(tokens); |
| } |
| ExprKind::WhileLet(ref pat, ref expr, ref body, ref label) => { |
| if let Some(ref label) = *label { |
| label.to_tokens(tokens); |
| tokens.append(":"); |
| } |
| tokens.append("while"); |
| tokens.append("let"); |
| pat.to_tokens(tokens); |
| tokens.append("="); |
| expr.to_tokens(tokens); |
| body.to_tokens(tokens); |
| } |
| ExprKind::ForLoop(ref pat, ref expr, ref body, ref label) => { |
| if let Some(ref label) = *label { |
| label.to_tokens(tokens); |
| tokens.append(":"); |
| } |
| tokens.append("for"); |
| pat.to_tokens(tokens); |
| tokens.append("in"); |
| expr.to_tokens(tokens); |
| body.to_tokens(tokens); |
| } |
| ExprKind::Loop(ref body, ref label) => { |
| if let Some(ref label) = *label { |
| label.to_tokens(tokens); |
| tokens.append(":"); |
| } |
| tokens.append("loop"); |
| body.to_tokens(tokens); |
| } |
| ExprKind::Match(ref expr, ref arms) => { |
| tokens.append("match"); |
| expr.to_tokens(tokens); |
| tokens.append("{"); |
| tokens.append_all(arms); |
| tokens.append("}"); |
| } |
| ExprKind::Closure(capture, ref decl, ref expr) => { |
| capture.to_tokens(tokens); |
| tokens.append("|"); |
| for (i, input) in decl.inputs.iter().enumerate() { |
| if i > 0 { |
| tokens.append(","); |
| } |
| match *input { |
| FnArg::Captured(ref pat, Ty::Infer) => { |
| pat.to_tokens(tokens); |
| } |
| _ => input.to_tokens(tokens), |
| } |
| } |
| tokens.append("|"); |
| match decl.output { |
| FunctionRetTy::Default => { /* nothing */ } |
| FunctionRetTy::Ty(ref ty) => { |
| tokens.append("->"); |
| ty.to_tokens(tokens); |
| } |
| } |
| expr.to_tokens(tokens); |
| } |
| ExprKind::Block(rules, ref block) => { |
| rules.to_tokens(tokens); |
| block.to_tokens(tokens); |
| } |
| ExprKind::Assign(ref var, ref expr) => { |
| var.to_tokens(tokens); |
| tokens.append("="); |
| expr.to_tokens(tokens); |
| } |
| ExprKind::AssignOp(op, ref var, ref expr) => { |
| var.to_tokens(tokens); |
| tokens.append(op.assign_op().unwrap()); |
| expr.to_tokens(tokens); |
| } |
| ExprKind::Field(ref expr, ref field) => { |
| expr.to_tokens(tokens); |
| tokens.append("."); |
| field.to_tokens(tokens); |
| } |
| ExprKind::TupField(ref expr, field) => { |
| expr.to_tokens(tokens); |
| tokens.append("."); |
| tokens.append(&field.to_string()); |
| } |
| ExprKind::Index(ref expr, ref index) => { |
| expr.to_tokens(tokens); |
| tokens.append("["); |
| index.to_tokens(tokens); |
| tokens.append("]"); |
| } |
| ExprKind::Range(ref from, ref to, limits) => { |
| from.to_tokens(tokens); |
| match limits { |
| RangeLimits::HalfOpen => tokens.append(".."), |
| RangeLimits::Closed => tokens.append("..."), |
| } |
| to.to_tokens(tokens); |
| } |
| ExprKind::Path(None, ref path) => path.to_tokens(tokens), |
| ExprKind::Path(Some(ref qself), ref path) => { |
| tokens.append("<"); |
| qself.ty.to_tokens(tokens); |
| if qself.position > 0 { |
| tokens.append("as"); |
| for (i, segment) in path.segments |
| .iter() |
| .take(qself.position) |
| .enumerate() { |
| if i > 0 || path.global { |
| tokens.append("::"); |
| } |
| segment.to_tokens(tokens); |
| } |
| } |
| tokens.append(">"); |
| for segment in path.segments.iter().skip(qself.position) { |
| tokens.append("::"); |
| segment.to_tokens(tokens); |
| } |
| } |
| ExprKind::AddrOf(mutability, ref expr) => { |
| tokens.append("&"); |
| mutability.to_tokens(tokens); |
| expr.to_tokens(tokens); |
| } |
| ExprKind::Break(ref opt_label, ref opt_val) => { |
| tokens.append("break"); |
| opt_label.to_tokens(tokens); |
| opt_val.to_tokens(tokens); |
| } |
| ExprKind::Continue(ref opt_label) => { |
| tokens.append("continue"); |
| opt_label.to_tokens(tokens); |
| } |
| ExprKind::Ret(ref opt_expr) => { |
| tokens.append("return"); |
| opt_expr.to_tokens(tokens); |
| } |
| ExprKind::Mac(ref mac) => mac.to_tokens(tokens), |
| ExprKind::Struct(ref path, ref fields, ref base) => { |
| path.to_tokens(tokens); |
| tokens.append("{"); |
| tokens.append_separated(fields, ","); |
| if let Some(ref base) = *base { |
| if !fields.is_empty() { |
| tokens.append(","); |
| } |
| tokens.append(".."); |
| base.to_tokens(tokens); |
| } |
| tokens.append("}"); |
| } |
| ExprKind::Repeat(ref expr, ref times) => { |
| tokens.append("["); |
| expr.to_tokens(tokens); |
| tokens.append(";"); |
| times.to_tokens(tokens); |
| tokens.append("]"); |
| } |
| ExprKind::Paren(ref expr) => { |
| tokens.append("("); |
| expr.to_tokens(tokens); |
| tokens.append(")"); |
| } |
| ExprKind::Try(ref expr) => { |
| expr.to_tokens(tokens); |
| tokens.append("?"); |
| } |
| } |
| } |
| } |
| |
| impl ToTokens for FieldValue { |
| fn to_tokens(&self, tokens: &mut Tokens) { |
| self.ident.to_tokens(tokens); |
| if !self.is_shorthand { |
| tokens.append(":"); |
| self.expr.to_tokens(tokens); |
| } |
| } |
| } |
| |
| impl ToTokens for Arm { |
| fn to_tokens(&self, tokens: &mut Tokens) { |
| for attr in &self.attrs { |
| attr.to_tokens(tokens); |
| } |
| tokens.append_separated(&self.pats, "|"); |
| if let Some(ref guard) = self.guard { |
| tokens.append("if"); |
| guard.to_tokens(tokens); |
| } |
| tokens.append("=>"); |
| self.body.to_tokens(tokens); |
| match self.body.node { |
| ExprKind::Block(Unsafety::Normal, _) => { |
| // no comma |
| } |
| _ => tokens.append(","), |
| } |
| } |
| } |
| |
| impl ToTokens for Pat { |
| fn to_tokens(&self, tokens: &mut Tokens) { |
| match *self { |
| Pat::Wild => tokens.append("_"), |
| Pat::Ident(mode, ref ident, ref subpat) => { |
| mode.to_tokens(tokens); |
| ident.to_tokens(tokens); |
| if let Some(ref subpat) = *subpat { |
| tokens.append("@"); |
| subpat.to_tokens(tokens); |
| } |
| } |
| Pat::Struct(ref path, ref fields, dots) => { |
| path.to_tokens(tokens); |
| tokens.append("{"); |
| tokens.append_separated(fields, ","); |
| if dots { |
| if !fields.is_empty() { |
| tokens.append(","); |
| } |
| tokens.append(".."); |
| } |
| tokens.append("}"); |
| } |
| Pat::TupleStruct(ref path, ref pats, dotpos) => { |
| path.to_tokens(tokens); |
| tokens.append("("); |
| match dotpos { |
| Some(pos) => { |
| if pos > 0 { |
| tokens.append_separated(&pats[..pos], ","); |
| tokens.append(","); |
| } |
| tokens.append(".."); |
| if pos < pats.len() { |
| tokens.append(","); |
| tokens.append_separated(&pats[pos..], ","); |
| } |
| } |
| None => tokens.append_separated(pats, ","), |
| } |
| tokens.append(")"); |
| } |
| Pat::Path(None, ref path) => path.to_tokens(tokens), |
| Pat::Path(Some(ref qself), ref path) => { |
| tokens.append("<"); |
| qself.ty.to_tokens(tokens); |
| if qself.position > 0 { |
| tokens.append("as"); |
| for (i, segment) in path.segments |
| .iter() |
| .take(qself.position) |
| .enumerate() { |
| if i > 0 || path.global { |
| tokens.append("::"); |
| } |
| segment.to_tokens(tokens); |
| } |
| } |
| tokens.append(">"); |
| for segment in path.segments.iter().skip(qself.position) { |
| tokens.append("::"); |
| segment.to_tokens(tokens); |
| } |
| } |
| Pat::Tuple(ref pats, dotpos) => { |
| tokens.append("("); |
| match dotpos { |
| Some(pos) => { |
| if pos > 0 { |
| tokens.append_separated(&pats[..pos], ","); |
| tokens.append(","); |
| } |
| tokens.append(".."); |
| if pos < pats.len() { |
| tokens.append(","); |
| tokens.append_separated(&pats[pos..], ","); |
| } |
| } |
| None => { |
| tokens.append_separated(pats, ","); |
| if pats.len() == 1 { |
| tokens.append(","); |
| } |
| } |
| } |
| tokens.append(")"); |
| } |
| Pat::Box(ref inner) => { |
| tokens.append("box"); |
| inner.to_tokens(tokens); |
| } |
| Pat::Ref(ref target, mutability) => { |
| tokens.append("&"); |
| mutability.to_tokens(tokens); |
| target.to_tokens(tokens); |
| } |
| Pat::Lit(ref lit) => lit.to_tokens(tokens), |
| Pat::Range(ref lo, ref hi) => { |
| lo.to_tokens(tokens); |
| tokens.append("..."); |
| hi.to_tokens(tokens); |
| } |
| Pat::Slice(ref before, ref rest, ref after) => { |
| tokens.append("["); |
| tokens.append_separated(before, ","); |
| if let Some(ref rest) = *rest { |
| if !before.is_empty() { |
| tokens.append(","); |
| } |
| if **rest != Pat::Wild { |
| rest.to_tokens(tokens); |
| } |
| tokens.append(".."); |
| if !after.is_empty() { |
| tokens.append(","); |
| } |
| tokens.append_separated(after, ","); |
| } |
| tokens.append("]"); |
| } |
| Pat::Mac(ref mac) => mac.to_tokens(tokens), |
| } |
| } |
| } |
| |
| impl ToTokens for FieldPat { |
| fn to_tokens(&self, tokens: &mut Tokens) { |
| if !self.is_shorthand { |
| self.ident.to_tokens(tokens); |
| tokens.append(":"); |
| } |
| self.pat.to_tokens(tokens); |
| } |
| } |
| |
| impl ToTokens for BindingMode { |
| fn to_tokens(&self, tokens: &mut Tokens) { |
| match *self { |
| BindingMode::ByRef(Mutability::Immutable) => { |
| tokens.append("ref"); |
| } |
| BindingMode::ByRef(Mutability::Mutable) => { |
| tokens.append("ref"); |
| tokens.append("mut"); |
| } |
| BindingMode::ByValue(Mutability::Immutable) => {} |
| BindingMode::ByValue(Mutability::Mutable) => { |
| tokens.append("mut"); |
| } |
| } |
| } |
| } |
| |
| impl ToTokens for CaptureBy { |
| fn to_tokens(&self, tokens: &mut Tokens) { |
| match *self { |
| CaptureBy::Value => tokens.append("move"), |
| CaptureBy::Ref => { |
| // nothing |
| } |
| } |
| } |
| } |
| |
| impl ToTokens for Block { |
| fn to_tokens(&self, tokens: &mut Tokens) { |
| tokens.append("{"); |
| tokens.append_all(&self.stmts); |
| tokens.append("}"); |
| } |
| } |
| |
| impl ToTokens for Stmt { |
| fn to_tokens(&self, tokens: &mut Tokens) { |
| match *self { |
| Stmt::Local(ref local) => local.to_tokens(tokens), |
| Stmt::Item(ref item) => item.to_tokens(tokens), |
| Stmt::Expr(ref expr) => expr.to_tokens(tokens), |
| Stmt::Semi(ref expr) => { |
| expr.to_tokens(tokens); |
| tokens.append(";"); |
| } |
| Stmt::Mac(ref mac) => { |
| let (ref mac, style, ref attrs) = **mac; |
| tokens.append_all(attrs.outer()); |
| mac.to_tokens(tokens); |
| match style { |
| MacStmtStyle::Semicolon => tokens.append(";"), |
| MacStmtStyle::Braces | MacStmtStyle::NoBraces => { |
| // no semicolon |
| } |
| } |
| } |
| } |
| } |
| } |
| |
| impl ToTokens for Local { |
| fn to_tokens(&self, tokens: &mut Tokens) { |
| tokens.append_all(self.attrs.outer()); |
| tokens.append("let"); |
| self.pat.to_tokens(tokens); |
| if let Some(ref ty) = self.ty { |
| tokens.append(":"); |
| ty.to_tokens(tokens); |
| } |
| if let Some(ref init) = self.init { |
| tokens.append("="); |
| init.to_tokens(tokens); |
| } |
| tokens.append(";"); |
| } |
| } |
| } |
