Module v1 Copy item path Source 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. deref Experimental Unstable placeholder for deref patterns. format_args_nl Experimental Same as format_args 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. Option The Option type. See the module level documentation for more. Result Result is a type that represents either success (OkErrAsMut 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 AsyncFnMut An async-aware version of the FnMut AsyncFnOnce An async-aware version of the FnOnce Clone A common trait that allows explicit creation of a duplicate value. Copy Types whose values can be duplicated simply by copying bits. Default A trait for giving a type a useful default value. DoubleEndedIterator An iterator able to yield elements from both ends. Drop Custom code within the destructor. Eq Trait for comparisons corresponding to equivalence relations . ExactSizeIterator 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 IntoIterator Conversion into an Iterator Iterator A trait for dealing with iterators. Ord Trait for types that form a total order . PartialEq Trait for comparisons using the equality operator. PartialOrd 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. 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. 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
to an item with a body. This list will be used in that body 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. 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 Ordhere . PartialEq Derive macro generating an impl of the trait PartialEqhere . PartialOrd Derive macro generating an impl of the trait PartialOrdhere .