Module builtin

Definitions of built-in macros.

Most of the macro properties (stability, visibility, etc.) are taken from the source code here, with exception of expansion functions transforming macro inputs into outputs, those functions are provided by the compiler.

Macros

derefExperimental

Unstable placeholder for deref patterns.

type_ascribeExperimental

Unstable placeholder for type ascription.

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_handlerExperimental

Attribute macro applied to a function to register it as a handler for allocation failure.

autodiff_forwardExperimental

This macro uses forward-mode automatic differentiation to generate a new function. It may only be applied to a function. The new function will compute the derivative of the function to which the macro was applied.

autodiff_reverseExperimental

This macro uses reverse-mode automatic differentiation to generate a new function. It may only be applied to a function. The new function will compute the derivative of the function to which the macro was applied.

benchExperimental

Attribute macro applied to a function to turn it into a benchmark test.

cfg_accessibleExperimental

Keeps the item it’s applied to if the passed path is accessible, and removes it otherwise.

cfg_evalExperimental

Expands all #[cfg] and #[cfg_attr] attributes in the code fragment it’s applied to.

contracts_ensuresExperimental

Attribute macro applied to a function to give it a post-condition.

contracts_requiresExperimental

Attribute macro applied to a function to give it a precondition.

define_opaqueExperimental

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_constExperimental

Attribute macro used to apply derive macros for implementing traits in a const context.

test_caseExperimental

An implementation detail of the #[test] and #[bench] macros.