///
/// **Example:**
/// ```rust
- /// // Bad
/// let x = 3.14;
/// let y = 1_f64 / x;
- ///
- /// // Good
+ /// ```
+ /// Use predefined constants instead:
+ /// ```rust
/// let x = std::f32::consts::PI;
/// let y = std::f64::consts::FRAC_1_PI;
/// ```
declare_lint_pass!(ApproxConstant => [APPROX_CONSTANT]);
-impl<'a, 'tcx> LateLintPass<'a, 'tcx> for ApproxConstant {
- fn check_expr(&mut self, cx: &LateContext<'a, 'tcx>, e: &'tcx Expr<'_>) {
+impl<'tcx> LateLintPass<'tcx> for ApproxConstant {
+ fn check_expr(&mut self, cx: &LateContext<'tcx>, e: &'tcx Expr<'_>) {
if let ExprKind::Lit(lit) = &e.kind {
check_lit(cx, &lit.node, e);
}
}
}
-fn check_lit(cx: &LateContext<'_, '_>, lit: &LitKind, e: &Expr<'_>) {
+fn check_lit(cx: &LateContext<'_>, lit: &LitKind, e: &Expr<'_>) {
match *lit {
LitKind::Float(s, LitFloatType::Suffixed(fty)) => match fty {
FloatTy::F32 => check_known_consts(cx, e, s, "f32"),
}
}
-fn check_known_consts(cx: &LateContext<'_, '_>, e: &Expr<'_>, s: symbol::Symbol, module: &str) {
+fn check_known_consts(cx: &LateContext<'_>, e: &Expr<'_>, s: symbol::Symbol, module: &str) {
let s = s.as_str();
if s.parse::<f64>().is_ok() {
for &(constant, name, min_digits) in &KNOWN_CONSTS {