apply - call a procedure with a list of arguments
(import (rnrs)) ;R6RS
(import (rnrs base)) ;R6RS
(import (scheme r5rs)) ;R7RS
(import (scheme base)) ;R7RS
(apply procedure obj ... pair)
The apply procedure calls procedure with the elements of the list
(append (list obj ...) pair)
as the actual arguments.
apply returns the values returned by procedure when
procedure is called in the manner above.
apply is usually used to call a procedure where the set of arguments to
give to the procedure is not known ahead of time. apply can also be
used to perform a simple "fold" over a list of items if
procedure can take an arbitrary number of arguments. For example:
(apply + (list 1 2 3 4)) => 10
This procedure can raise exceptions with the following condition types:
- &assertion (R6RS)
- The wrong number of arguments was passed or an argument was outside its
domain.
- R7RS
- The assertions described above are errors. Implementations may signal an
error, extend the procedure's domain of definition to include such
arguments, or fail catastrophically.
R4RS, IEEE Scheme, R5RS, R6RS, R7RS