with-modification-check-macro Macro

Summary

Provides a way to check whether there was any "modification" during execution of a body of code.

Package

system

Signature

with-modification-check-macro macro-name modification-place &body body

Arguments

Description

The macro with-modification-check-macro, together with the macro with-modification-change, provides a way for a body of code body to execute and check whether there was any "modification" during this execution, where modification is execution of some other piece of code.

with-modification-check-macro defines a lexical macro (by macrolet) with the name macro-name which takes no arguments, and is used to check whether there was any change since entering the body.

modification-place must be initialized to the fixnum 0 before being used, and must not be modified by any code except with-modification-change.

See 19.13.2 Aids for implementing modification checks for the full description and an example.

Notes

modification-place does not need to be one of the places defined for low level atomic operations.

See also

with-modification-change