Expand description
The 2015 version of the core prelude.
See the module-level documentation for more.
Macros§
- assert
- Asserts that a boolean expression is
true
at runtime. - cfg
- Evaluates boolean combinations of configuration flags at compile-time.
- column
- Expands to the column number at which it was invoked.
- compile_
error - Causes compilation to fail with the given error message when encountered.
- concat
- Concatenates literals into a static string slice.
- env
- Inspects an environment variable at compile time.
- file
- Expands to the file name in which it was invoked.
- format_
args - Constructs parameters for the other string-formatting macros.
- include
- Parses a file as an expression or an item according to the context.
- include_
bytes - Includes a file as a reference to a byte array.
- include_
str - Includes a UTF-8 encoded file as a string.
- line
- Expands to the line number on which it was invoked.
- module_
path - Expands to a string that represents the current module path.
- option_
env - Optionally inspects an environment variable at compile time.
- stringify
- Stringifies its arguments.
- concat_
bytes Experimental - Concatenates literals into a byte slice.
- concat_
idents Experimental - Concatenates identifiers into one identifier.
- deref
Experimental - Unstable placeholder for deref patterns.
- format_
args_ nl Experimental - Same as
format_args
, but adds a newline in the end. - log_
syntax Experimental - Prints passed tokens into the standard output.
- trace_
macros Experimental - Enables or disables tracing functionality used for debugging other macros.
- type_
ascribe Experimental - Unstable placeholder for type ascription.
Enums§
- Option
- The
Option
type. See the module level documentation for more. - Result
Result
is a type that represents either success (Ok
) or failure (Err
).
Traits§
- AsMut
- Used to do a cheap mutable-to-mutable reference conversion.
- AsRef
- Used to do a cheap reference-to-reference conversion.
- AsyncFn
- An async-aware version of the
Fn
trait. - Async
FnMut - An async-aware version of the
FnMut
trait. - Async
FnOnce - An async-aware version of the
FnOnce
trait. - Clone
- A common trait for the ability to explicitly duplicate an object.
- Copy
- Types whose values can be duplicated simply by copying bits.
- Default
- A trait for giving a type a useful default value.
- Double
Ended Iterator - An iterator able to yield elements from both ends.
- Drop
- Custom code within the destructor.
- Eq
- Trait for comparisons corresponding to equivalence relations.
- Exact
Size Iterator - An iterator that knows its exact length.
- Extend
- Extend a collection with the contents of an iterator.
- Fn
- The version of the call operator that takes an immutable receiver.
- FnMut
- The version of the call operator that takes a mutable receiver.
- FnOnce
- The version of the call operator that takes a by-value receiver.
- From
- Used to do value-to-value conversions while consuming the input value. It is the reciprocal of
Into
. - Into
- A value-to-value conversion that consumes the input value. The
opposite of
From
. - Into
Iterator - Conversion into an
Iterator
. - Iterator
- A trait for dealing with iterators.
- Ord
- Trait for types that form a total order.
- Partial
Eq - Trait for comparisons using the equality operator.
- Partial
Ord - Trait for types that form a partial order.
- Send
- Types that can be transferred across thread boundaries.
- Sized
- Types with a constant size known at compile time.
- Sync
- Types for which it is safe to share references between threads.
- Unpin
- Types that do not require any pinning guarantees.
Functions§
- align_
of - Returns the ABI-required minimum alignment of a type in bytes.
- align_
of_ val - Returns the ABI-required minimum alignment of the type of the value that
val
points to in bytes. - drop
- Disposes of a value.
- size_of
- Returns the size of a type in bytes.
- size_
of_ val - Returns the size of the pointed-to value in bytes.
Attribute Macros§
- derive
- Attribute macro used to apply derive macros.
- global_
allocator - Attribute macro applied to a static to register it as a global allocator.
- test
- Attribute macro applied to a function to turn it into a unit test.
- alloc_
error_ handler Experimental - Attribute macro applied to a function to register it as a handler for allocation failure.
- bench
Experimental - Attribute macro applied to a function to turn it into a benchmark test.
- cfg_
accessible Experimental - Keeps the item it’s applied to if the passed path is accessible, and removes it otherwise.
- cfg_
eval Experimental - Expands all
#[cfg]
and#[cfg_attr]
attributes in the code fragment it’s applied to. - define_
opaque Experimental - Provide a list of type aliases and other opaque-type-containing type definitions. This list will be used in the body of the item it is applied to to define opaque types’ hidden types. Can only be applied to things that have bodies.
- derive_
const Experimental - Attribute macro used to apply derive macros for implementing traits in a const context.
- test_
case Experimental - An implementation detail of the
#[test]
and#[bench]
macros.
Derive Macros§
- Clone
- Derive macro generating an impl of the trait
Clone
. - Copy
- Derive macro generating an impl of the trait
Copy
. - Debug
- Derive macro generating an impl of the trait
Debug
. - Default
- Derive macro generating an impl of the trait
Default
. - Eq
- Derive macro generating an impl of the trait
Eq
. - Hash
- Derive macro generating an impl of the trait
Hash
. - Ord
- Derive macro generating an impl of the trait
Ord
. The behavior of this macro is described in detail here. - Partial
Eq - Derive macro generating an impl of the trait
PartialEq
. The behavior of this macro is described in detail here. - Partial
Ord - Derive macro generating an impl of the trait
PartialOrd
. The behavior of this macro is described in detail here.