Struct clang_sys::CXModule
[−]
[src]
pub struct CXModule(pub *mut c_void);
Methods from Deref<Target=*mut c_void>
fn is_null(self) -> bool
1.0.0
Returns true if the pointer is null.
Examples
Basic usage:
let s: &str = "Follow the rabbit"; let ptr: *const u8 = s.as_ptr(); assert!(!ptr.is_null());
unsafe fn as_ref(self) -> Option<&'a T>
1.9.0
Returns None
if the pointer is null, or else returns a reference to
the value wrapped in Some
.
Safety
While this method and its mutable counterpart are useful for null-safety, it is important to note that this is still an unsafe operation because the returned value could be pointing to invalid memory.
Additionally, the lifetime 'a
returned is arbitrarily chosen and does
not necessarily reflect the actual lifetime of the data.
Examples
Basic usage:
let val: *const u8 = &10u8 as *const u8; unsafe { if let Some(val_back) = val.as_ref() { println!("We got back the value: {}!", val_back); } }
unsafe fn offset(self, count: isize) -> *const T
1.0.0
Calculates the offset from a pointer. count
is in units of T; e.g. a
count
of 3 represents a pointer offset of 3 * sizeof::<T>()
bytes.
Safety
Both the starting and resulting pointer must be either in bounds or one byte past the end of an allocated object. If either pointer is out of bounds or arithmetic overflow occurs then any further use of the returned value will result in undefined behavior.
Examples
Basic usage:
let s: &str = "123"; let ptr: *const u8 = s.as_ptr(); unsafe { println!("{}", *ptr.offset(1) as char); println!("{}", *ptr.offset(2) as char); }
fn wrapping_offset(self, count: isize) -> *const T
ptr_wrapping_offset
)Calculates the offset from a pointer using wrapping arithmetic.
count
is in units of T; e.g. a count
of 3 represents a pointer
offset of 3 * sizeof::<T>()
bytes.
Safety
The resulting pointer does not need to be in bounds, but it is
potentially hazardous to dereference (which requires unsafe
).
Always use .offset(count)
instead when possible, because offset
allows the compiler to optimize better.
Examples
Basic usage:
#![feature(ptr_wrapping_offset)] // Iterate using a raw pointer in increments of two elements let data = [1u8, 2, 3, 4, 5]; let mut ptr: *const u8 = data.as_ptr(); let step = 2; let end_rounded_up = ptr.wrapping_offset(6); // This loop prints "1, 3, 5, " while ptr != end_rounded_up { unsafe { print!("{}, ", *ptr); } ptr = ptr.wrapping_offset(step); }
Trait Implementations
impl Copy for CXModule
[src]
impl Clone for CXModule
[src]
fn clone(&self) -> CXModule
Returns a copy of the value. Read more
fn clone_from(&mut self, source: &Self)
1.0.0
Performs copy-assignment from source
. Read more