| | | atomic-pushnew | |
|
| item place
&key key test test-not
=> new-place-value | [Macro] |
Purpose
As an atomic operation, when item is not
the same as any element in the list stored in place, prepend
item to the list and store the updated list in place.
Package :portable-threads
Module :portable-threads
Arguments and values
| item | An object | |
| place | A form which is suitable for use as a generalized reference that contains a proper list | |
| key | A function of one argument, or nil (default is nil)
| |
| test | A function of two arguments that returns a
generalized boolean (default is #'eql)
| |
| test-not | A function of two arguments that returns a
generalized boolean (use of :test-not is deprecated)
| |
| new-place-value | A proper list |
Returns
The new value of place.
See also
as-atomic-operation
atomic-delete
atomic-flush
atomic-pop
atomic-push
Examples
> list (1 2 3) > (atomic-pushnew 2 list) (1 2 3) > (atomic-pushnew 10 list) (10 1 2 3) >
The GBBopen Project
| | | atomic-pushnew | |