pub trait Flags<T: Into<Self>>:
Copy
+ Clone
+ Debug
+ Send
+ Sync
+ 'static
+ PartialEq
+ Eq
+ BitAnd
+ BitOr
+ BitXor
+ BitAndAssign
+ BitOrAssign
+ BitXorAssign
+ Notwhere
<Self as BitAnd>::Output: PartialEq<Self> + Eq + Into<Self>,
<Self as BitOr>::Output: PartialEq<Self> + Eq + Into<Self>,
<Self as BitXor>::Output: PartialEq<Self> + Eq + Into<Self>,
<Self as Not>::Output: Into<Self>,{
// Provided methods
fn has_flag(&self, flag: T) -> bool { ... }
fn set_flag(&mut self, flag: T) { ... }
fn unset_flag(&mut self, flag: T) { ... }
}Expand description
Implemented on types that are capable of bitwise twiddling as a way of turning on and off
different bit-specific flags, such as u8, u16, u32, u64, etc.
To integrate with Flags, custom enum types should implent From<T> where T is the
type that implements Flags. You can then call has_flag, set_flag, and unset_flag
on T using flags defined by the custom enum type, like so:
use bit_flags::Flags;
#[derive(Copy, Clone, Debug, PartialEq, Eq)]
enum MyFlags {
Flag1 = 1 << 0, // 0b00000001
Flag2 = 1 << 1, // 0b00000010
Flag3 = 1 << 2, // 0b00000100
Flag4 = 1 << 3, // 0b00001000
}
impl From<MyFlags> for u8 {
fn from(flag: MyFlags) -> Self {
flag as u8
}
}
let mut flags: u8 = MyFlags::Flag1 as u8 | MyFlags::Flag2 as u8;
assert!(flags.has_flag(MyFlags::Flag1));
assert!(flags.has_flag(MyFlags::Flag2));
assert!(!flags.has_flag(MyFlags::Flag3));
flags.set_flag(MyFlags::Flag3);
assert!(flags.has_flag(MyFlags::Flag3));
flags.set_flag(MyFlags::Flag1);
assert!(flags.has_flag(MyFlags::Flag1));
flags.unset_flag(MyFlags::Flag2);
assert!(!flags.has_flag(MyFlags::Flag2));
// You can also use the flags directly with bitwise operations:
flags |= MyFlags::Flag4 as u8; // Set Flag4
flags &= !(MyFlags::Flag1 as u8); // Unset Flag1
assert!(flags.has_flag(MyFlags::Flag4));
assert!(!flags.has_flag(MyFlags::Flag1));
assert!(flags.has_flag(MyFlags::Flag3));
assert!(!flags.has_flag(MyFlags::Flag2));You can also use multi-byte flags:
use bit_flags::Flags;
#[repr(u16)]
#[derive(Copy, Clone, Debug, PartialEq, Eq)]
enum MyFlags {
Flag1 = 1 << 0, // 0b0000000000000001
Flag2 = 1 << 1, // 0b0000000000000010
Flag3 = 1 << 2, // 0b0000000000000100
Flag4 = 1 << 3, // 0b0000000000001000
Flag5 = 1 << 4, // 0b0000000000010000
Flag6 = 1 << 5, // 0b0000000000100000
Flag7 = 1 << 6, // 0b0000000001000000
Flag8 = 1 << 7, // 0b0000000010000000
Flag9 = 1 << 8, // 0b0000000100000000
Flag10 = 1 << 9, // 0b0000001000000000
Flag11 = 1 << 10, // 0b0000010000000000
Flag12 = 1 << 11, // 0b0000100000000000
Flag13 = 1 << 12, // 0b0001000000000000
Flag14 = 1 << 13, // 0b0010000000000000
Flag15 = 1 << 14, // 0b0100000000000000
Flag16 = 1 << 15, // 0b1000000000000000
}
impl From<MyFlags> for u16 {
fn from(flag: MyFlags) -> Self {
flag as u16
}
}
let mut flags: u16 = MyFlags::Flag1 as u16 | MyFlags::Flag2 as u16;
assert!(flags.has_flag(MyFlags::Flag1));
assert!(flags.has_flag(MyFlags::Flag2));
assert!(!flags.has_flag(MyFlags::Flag3));
flags.set_flag(MyFlags::Flag15);
assert!(flags.has_flag(MyFlags::Flag15));
flags.unset_flag(MyFlags::Flag1);
assert!(!flags.has_flag(MyFlags::Flag1));
assert_eq!(flags, MyFlags::Flag2 as u16 | MyFlags::Flag15 as u16);Provided Methods§
fn has_flag(&self, flag: T) -> bool
Sourcefn unset_flag(&mut self, flag: T)
fn unset_flag(&mut self, flag: T)
Unsets the specified flag on this flag set.
Dyn Compatibility§
This trait is not dyn compatible.
In older versions of Rust, dyn compatibility was called "object safety".