##Lints
There are 48 lints included in this crate:
-name | default | meaning
--------------------------|---------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------
-approx_constant | warn | the approximate of a known float constant (in `std::f64::consts` or `std::f32::consts`) is found; suggests to use the constant
-bad_bit_mask | deny | expressions of the form `_ & mask == select` that will only ever return `true` or `false` (because in the example `select` containing bits that `mask` doesn't have)
-box_vec | warn | usage of `Box<Vec<T>>`, vector elements are already on the heap
-cast_possible_truncation | allow | casts that may cause truncation of the value, e.g `x as u8` where `x: u32`, or `x as i32` where `x: f32`
-cast_possible_wrap | allow | casts that may cause wrapping around the value, e.g `x as i32` where `x: u32` and `x > i32::MAX`
-cast_precision_loss | allow | casts that cause loss of precision, e.g `x as f32` where `x: u64`
-cast_sign_loss | allow | casts from signed types to unsigned types, e.g `x as u32` where `x: i32`
-cmp_nan | deny | comparisons to NAN (which will always return false, which is probably not intended)
-cmp_owned | warn | creating owned instances for comparing with others, e.g. `x == "foo".to_string()`
-collapsible_if | warn | two nested `if`-expressions can be collapsed into one, e.g. `if x { if y { foo() } }` can be written as `if x && y { foo() }`
-eq_op | warn | equal operands on both sides of a comparison or bitwise combination (e.g. `x == x`)
-explicit_iter_loop | warn | for-looping over `_.iter()` or `_.iter_mut()` when `&_` or `&mut _` would do
-float_cmp | warn | using `==` or `!=` on float values (as floating-point operations usually involve rounding errors, it is always better to check for approximate equality within small bounds)
-identity_op | warn | using identity operations, e.g. `x + 0` or `y / 1`
-ineffective_bit_mask | warn | expressions where a bit mask will be rendered useless by a comparison, e.g. `(x | 1) > 2`
-inline_always | warn | `#[inline(always)]` is a bad idea in most cases
-iter_next_loop | warn | for-looping over `_.next()` which is probably not intended
-len_without_is_empty | warn | traits and impls that have `.len()` but not `.is_empty()`
-len_zero | warn | checking `.len() == 0` or `.len() > 0` (or similar) when `.is_empty()` could be used instead
-let_and_return | warn | creating a let-binding and then immediately returning it like `let x = expr; x` at the end of a function
-let_unit_value | warn | creating a let binding to a value of unit type, which usually can't be used afterwards
-linkedlist | warn | usage of LinkedList, usually a vector is faster, or a more specialized data structure like a RingBuf
-match_ref_pats | warn | a match has all arms prefixed with `&`; the match expression can be dereferenced instead
-modulo_one | warn | taking a number modulo 1, which always returns 0
-mut_mut | warn | usage of double-mut refs, e.g. `&mut &mut ...` (either copy'n'paste error, or shows a fundamental misunderstanding of references)
-needless_bool | warn | if-statements with plain booleans in the then- and else-clause, e.g. `if p { true } else { false }`
-needless_lifetimes | warn | using explicit lifetimes for references in function arguments when elision rules would allow omitting them
-needless_range_loop | warn | for-looping over a range of indices where an iterator over items would do
-needless_return | warn | using a return statement like `return expr;` where an expression would suffice
-non_ascii_literal | allow | using any literal non-ASCII chars in a string literal; suggests using the \\u escape instead
-option_unwrap_used | allow | using `Option.unwrap()`, which should at least get a better message using `expect()`
-precedence | warn | expressions where precedence may trip up the unwary reader of the source; suggests adding parentheses, e.g. `x << 2 + y` will be parsed as `x << (2 + y)`
-ptr_arg | allow | fn arguments of the type `&Vec<...>` or `&String`, suggesting to use `&[...]` or `&str` instead, respectively
-range_step_by_zero | warn | using Range::step_by(0), which produces an infinite iterator
-redundant_closure | warn | using redundant closures, i.e. `|a| foo(a)` (which can be written as just `foo`)
-result_unwrap_used | allow | using `Result.unwrap()`, which might be better handled
-shadow_reuse | allow | rebinding a name to an expression that re-uses the original value, e.g. `let x = x + 1`
-shadow_same | allow | rebinding a name to itself, e.g. `let mut x = &mut x`
-shadow_unrelated | warn | The name is re-bound without even using the original value
-single_match | warn | a match statement with a single nontrivial arm (i.e, where the other arm is `_ => {}`) is used; recommends `if let` instead
-str_to_string | warn | using `to_string()` on a str, which should be `to_owned()`
-string_add | allow | using `x + ..` where x is a `String`; suggests using `push_str()` instead
-string_add_assign | allow | using `x = x + ..` where x is a `String`; suggests using `push_str()` instead
-string_to_string | warn | calling `String.to_string()` which is a no-op
-toplevel_ref_arg | warn | a function argument is declared `ref` (i.e. `fn foo(ref x: u8)`, but not `fn foo((ref x, ref y): (u8, u8))`)
-type_complexity | warn | usage of very complex types; recommends factoring out parts into `type` definitions
-unit_cmp | warn | comparing unit values (which is always `true` or `false`, respectively)
-zero_width_space | deny | using a zero-width space in a string literal, which is confusing
+name | default | meaning
+-----------------------------------------------------------------------------------------------------|---------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------
+[approx_constant](https://github.com/Manishearth/rust-clippy/wiki#approx_constant) | warn | the approximate of a known float constant (in `std::f64::consts` or `std::f32::consts`) is found; suggests to use the constant
+[bad_bit_mask](https://github.com/Manishearth/rust-clippy/wiki#bad_bit_mask) | deny | expressions of the form `_ & mask == select` that will only ever return `true` or `false` (because in the example `select` containing bits that `mask` doesn't have)
+[box_vec](https://github.com/Manishearth/rust-clippy/wiki#box_vec) | warn | usage of `Box<Vec<T>>`, vector elements are already on the heap
+[cast_possible_truncation](https://github.com/Manishearth/rust-clippy/wiki#cast_possible_truncation) | allow | casts that may cause truncation of the value, e.g `x as u8` where `x: u32`, or `x as i32` where `x: f32`
+[cast_possible_wrap](https://github.com/Manishearth/rust-clippy/wiki#cast_possible_wrap) | allow | casts that may cause wrapping around the value, e.g `x as i32` where `x: u32` and `x > i32::MAX`
+[cast_precision_loss](https://github.com/Manishearth/rust-clippy/wiki#cast_precision_loss) | allow | casts that cause loss of precision, e.g `x as f32` where `x: u64`
+[cast_sign_loss](https://github.com/Manishearth/rust-clippy/wiki#cast_sign_loss) | allow | casts from signed types to unsigned types, e.g `x as u32` where `x: i32`
+[cmp_nan](https://github.com/Manishearth/rust-clippy/wiki#cmp_nan) | deny | comparisons to NAN (which will always return false, which is probably not intended)
+[cmp_owned](https://github.com/Manishearth/rust-clippy/wiki#cmp_owned) | warn | creating owned instances for comparing with others, e.g. `x == "foo".to_string()`
+[collapsible_if](https://github.com/Manishearth/rust-clippy/wiki#collapsible_if) | warn | two nested `if`-expressions can be collapsed into one, e.g. `if x { if y { foo() } }` can be written as `if x && y { foo() }`
+[eq_op](https://github.com/Manishearth/rust-clippy/wiki#eq_op) | warn | equal operands on both sides of a comparison or bitwise combination (e.g. `x == x`)
+[explicit_iter_loop](https://github.com/Manishearth/rust-clippy/wiki#explicit_iter_loop) | warn | for-looping over `_.iter()` or `_.iter_mut()` when `&_` or `&mut _` would do
+[float_cmp](https://github.com/Manishearth/rust-clippy/wiki#float_cmp) | warn | using `==` or `!=` on float values (as floating-point operations usually involve rounding errors, it is always better to check for approximate equality within small bounds)
+[identity_op](https://github.com/Manishearth/rust-clippy/wiki#identity_op) | warn | using identity operations, e.g. `x + 0` or `y / 1`
+[ineffective_bit_mask](https://github.com/Manishearth/rust-clippy/wiki#ineffective_bit_mask) | warn | expressions where a bit mask will be rendered useless by a comparison, e.g. `(x | 1) > 2`
+[inline_always](https://github.com/Manishearth/rust-clippy/wiki#inline_always) | warn | `#[inline(always)]` is a bad idea in most cases
+[iter_next_loop](https://github.com/Manishearth/rust-clippy/wiki#iter_next_loop) | warn | for-looping over `_.next()` which is probably not intended
+[len_without_is_empty](https://github.com/Manishearth/rust-clippy/wiki#len_without_is_empty) | warn | traits and impls that have `.len()` but not `.is_empty()`
+[len_zero](https://github.com/Manishearth/rust-clippy/wiki#len_zero) | warn | checking `.len() == 0` or `.len() > 0` (or similar) when `.is_empty()` could be used instead
+[let_and_return](https://github.com/Manishearth/rust-clippy/wiki#let_and_return) | warn | creating a let-binding and then immediately returning it like `let x = expr; x` at the end of a function
+[let_unit_value](https://github.com/Manishearth/rust-clippy/wiki#let_unit_value) | warn | creating a let binding to a value of unit type, which usually can't be used afterwards
+[linkedlist](https://github.com/Manishearth/rust-clippy/wiki#linkedlist) | warn | usage of LinkedList, usually a vector is faster, or a more specialized data structure like a RingBuf
+[match_ref_pats](https://github.com/Manishearth/rust-clippy/wiki#match_ref_pats) | warn | a match has all arms prefixed with `&`; the match expression can be dereferenced instead
+[modulo_one](https://github.com/Manishearth/rust-clippy/wiki#modulo_one) | warn | taking a number modulo 1, which always returns 0
+[mut_mut](https://github.com/Manishearth/rust-clippy/wiki#mut_mut) | warn | usage of double-mut refs, e.g. `&mut &mut ...` (either copy'n'paste error, or shows a fundamental misunderstanding of references)
+[needless_bool](https://github.com/Manishearth/rust-clippy/wiki#needless_bool) | warn | if-statements with plain booleans in the then- and else-clause, e.g. `if p { true } else { false }`
+[needless_lifetimes](https://github.com/Manishearth/rust-clippy/wiki#needless_lifetimes) | warn | using explicit lifetimes for references in function arguments when elision rules would allow omitting them
+[needless_range_loop](https://github.com/Manishearth/rust-clippy/wiki#needless_range_loop) | warn | for-looping over a range of indices where an iterator over items would do
+[needless_return](https://github.com/Manishearth/rust-clippy/wiki#needless_return) | warn | using a return statement like `return expr;` where an expression would suffice
+[non_ascii_literal](https://github.com/Manishearth/rust-clippy/wiki#non_ascii_literal) | allow | using any literal non-ASCII chars in a string literal; suggests using the \\u escape instead
+[option_unwrap_used](https://github.com/Manishearth/rust-clippy/wiki#option_unwrap_used) | allow | using `Option.unwrap()`, which should at least get a better message using `expect()`
+[precedence](https://github.com/Manishearth/rust-clippy/wiki#precedence) | warn | expressions where precedence may trip up the unwary reader of the source; suggests adding parentheses, e.g. `x << 2 + y` will be parsed as `x << (2 + y)`
+[ptr_arg](https://github.com/Manishearth/rust-clippy/wiki#ptr_arg) | allow | fn arguments of the type `&Vec<...>` or `&String`, suggesting to use `&[...]` or `&str` instead, respectively
+[range_step_by_zero](https://github.com/Manishearth/rust-clippy/wiki#range_step_by_zero) | warn | using Range::step_by(0), which produces an infinite iterator
+[redundant_closure](https://github.com/Manishearth/rust-clippy/wiki#redundant_closure) | warn | using redundant closures, i.e. `|a| foo(a)` (which can be written as just `foo`)
+[result_unwrap_used](https://github.com/Manishearth/rust-clippy/wiki#result_unwrap_used) | allow | using `Result.unwrap()`, which might be better handled
+[shadow_reuse](https://github.com/Manishearth/rust-clippy/wiki#shadow_reuse) | allow | rebinding a name to an expression that re-uses the original value, e.g. `let x = x + 1`
+[shadow_same](https://github.com/Manishearth/rust-clippy/wiki#shadow_same) | allow | rebinding a name to itself, e.g. `let mut x = &mut x`
+[shadow_unrelated](https://github.com/Manishearth/rust-clippy/wiki#shadow_unrelated) | warn | The name is re-bound without even using the original value
+[single_match](https://github.com/Manishearth/rust-clippy/wiki#single_match) | warn | a match statement with a single nontrivial arm (i.e, where the other arm is `_ => {}`) is used; recommends `if let` instead
+[str_to_string](https://github.com/Manishearth/rust-clippy/wiki#str_to_string) | warn | using `to_string()` on a str, which should be `to_owned()`
+[string_add](https://github.com/Manishearth/rust-clippy/wiki#string_add) | allow | using `x + ..` where x is a `String`; suggests using `push_str()` instead
+[string_add_assign](https://github.com/Manishearth/rust-clippy/wiki#string_add_assign) | allow | using `x = x + ..` where x is a `String`; suggests using `push_str()` instead
+[string_to_string](https://github.com/Manishearth/rust-clippy/wiki#string_to_string) | warn | calling `String.to_string()` which is a no-op
+[toplevel_ref_arg](https://github.com/Manishearth/rust-clippy/wiki#toplevel_ref_arg) | warn | a function argument is declared `ref` (i.e. `fn foo(ref x: u8)`, but not `fn foo((ref x, ref y): (u8, u8))`)
+[type_complexity](https://github.com/Manishearth/rust-clippy/wiki#type_complexity) | warn | usage of very complex types; recommends factoring out parts into `type` definitions
+[unit_cmp](https://github.com/Manishearth/rust-clippy/wiki#unit_cmp) | warn | comparing unit values (which is always `true` or `false`, respectively)
+[zero_width_space](https://github.com/Manishearth/rust-clippy/wiki#zero_width_space) | deny | using a zero-width space in a string literal, which is confusing
More to come, please [file an issue](https://github.com/Manishearth/rust-clippy/issues) if you have ideas!
projects / rust.git / commitdiff