/// The essential nodes of a desugared for loop as well as the entire span:
/// `for pat in arg { body }` becomes `(pat, arg, body)`. Return `(pat, arg, body, span)`.
pub struct ForLoop<'tcx> {
+ /// `for` loop item
pub pat: &'tcx hir::Pat<'tcx>,
+ /// `IntoIterator` argument
pub arg: &'tcx hir::Expr<'tcx>,
+ /// `for` loop body
pub body: &'tcx hir::Expr<'tcx>,
+ /// entire `for` loop span
pub span: Span,
}
impl<'tcx> ForLoop<'tcx> {
#[inline]
+ /// Parses a desugared `for` loop
pub fn hir(expr: &Expr<'tcx>) -> Option<Self> {
if_chain! {
if let hir::ExprKind::Match(iterexpr, arms, hir::MatchSource::ForLoopDesugar) = expr.kind;
}
}
+/// An `if` expression without `DropTemps`
pub struct If<'hir> {
+ /// `if` condition
pub cond: &'hir Expr<'hir>,
- pub r#else: Option<&'hir Expr<'hir>>,
+ /// `if` then expression
pub then: &'hir Expr<'hir>,
+ /// `else` expression
+ pub r#else: Option<&'hir Expr<'hir>>,
}
impl<'hir> If<'hir> {
#[inline]
+ /// Parses an `if` expression
pub const fn hir(expr: &Expr<'hir>) -> Option<Self> {
if let ExprKind::If(
Expr {
r#else,
) = expr.kind
{
- Some(Self { cond, r#else, then })
+ Some(Self { cond, then, r#else })
} else {
None
}
}
}
+/// An `if let` expression
pub struct IfLet<'hir> {
+ /// `if let` pattern
pub let_pat: &'hir Pat<'hir>,
+ /// `if let` scrutinee
pub let_expr: &'hir Expr<'hir>,
+ /// `if let` then expression
pub if_then: &'hir Expr<'hir>,
+ /// `if let` else expression
pub if_else: Option<&'hir Expr<'hir>>,
}
impl<'hir> IfLet<'hir> {
+ /// Parses an `if let` expression
pub fn hir(cx: &LateContext<'_>, expr: &Expr<'hir>) -> Option<Self> {
if let ExprKind::If(
Expr {
}
}
+/// An `if let` or `match` expression. Useful for lints that trigger on one or the other.
pub enum IfLetOrMatch<'hir> {
+ /// Any `match` expression
Match(&'hir Expr<'hir>, &'hir [Arm<'hir>], MatchSource),
/// scrutinee, pattern, then block, else block
IfLet(
}
impl<'hir> IfLetOrMatch<'hir> {
+ /// Parses an `if let` or `match` expression
pub fn parse(cx: &LateContext<'_>, expr: &Expr<'hir>) -> Option<Self> {
match expr.kind {
ExprKind::Match(expr, arms, source) => Some(Self::Match(expr, arms, source)),
}
}
+/// An `if` or `if let` expression
pub struct IfOrIfLet<'hir> {
+ /// `if` condition that is maybe a `let` expression
pub cond: &'hir Expr<'hir>,
- pub r#else: Option<&'hir Expr<'hir>>,
+ /// `if` then expression
pub then: &'hir Expr<'hir>,
+ /// `else` expression
+ pub r#else: Option<&'hir Expr<'hir>>,
}
impl<'hir> IfOrIfLet<'hir> {
#[inline]
+ /// Parses an `if` or `if let` expression
pub const fn hir(expr: &Expr<'hir>) -> Option<Self> {
if let ExprKind::If(cond, then, r#else) = expr.kind {
if let ExprKind::DropTemps(new_cond) = cond.kind {
});
}
if let ExprKind::Let(..) = cond.kind {
- return Some(Self { cond, r#else, then });
+ return Some(Self { cond, then, r#else });
}
}
None
}
}
+/// A desugared `while` loop
pub struct While<'hir> {
- pub if_cond: &'hir Expr<'hir>,
- pub if_then: &'hir Expr<'hir>,
- pub if_else: Option<&'hir Expr<'hir>>,
+ /// `while` loop condition
+ pub condition: &'hir Expr<'hir>,
+ /// `while` loop body
+ pub body: &'hir Expr<'hir>,
}
impl<'hir> While<'hir> {
#[inline]
+ /// Parses a desugared `while` loop
pub const fn hir(expr: &Expr<'hir>) -> Option<Self> {
if let ExprKind::Loop(
Block {
kind:
ExprKind::If(
Expr {
- kind: ExprKind::DropTemps(if_cond),
+ kind: ExprKind::DropTemps(condition),
..
},
- if_then,
- if_else_ref,
+ body,
+ _,
),
..
}),
_,
) = expr.kind
{
- let if_else = *if_else_ref;
- return Some(Self {
- if_cond,
- if_then,
- if_else,
- });
+ return Some(Self { condition, body });
}
None
}
}
+/// A desugared `while let` loop
pub struct WhileLet<'hir> {
- pub if_expr: &'hir Expr<'hir>,
+ /// `while let` loop item pattern
pub let_pat: &'hir Pat<'hir>,
+ /// `while let` loop scrutinee
pub let_expr: &'hir Expr<'hir>,
+ /// `while let` loop body
pub if_then: &'hir Expr<'hir>,
- pub if_else: Option<&'hir Expr<'hir>>,
}
impl<'hir> WhileLet<'hir> {
#[inline]
+ /// Parses a desugared `while let` loop
pub const fn hir(expr: &Expr<'hir>) -> Option<Self> {
if let ExprKind::Loop(
Block {
- expr: Some(if_expr), ..
+ expr:
+ Some(Expr {
+ kind:
+ ExprKind::If(
+ Expr {
+ kind: ExprKind::Let(let_pat, let_expr, _),
+ ..
+ },
+ if_then,
+ _,
+ ),
+ ..
+ }),
+ ..
},
_,
LoopSource::While,
_,
) = expr.kind
{
- if let Expr {
- kind:
- ExprKind::If(
- Expr {
- kind: ExprKind::Let(let_pat, let_expr, _),
- ..
- },
- if_then,
- if_else_ref,
- ),
- ..
- } = if_expr
- {
- let if_else = *if_else_ref;
- return Some(Self {
- if_expr,
- let_pat,
- let_expr,
- if_then,
- if_else,
- });
- }
+ return Some(Self {
+ let_pat,
+ let_expr,
+ if_then,
+ });
}
None
}