all

Lib.all : ('a -> bool) -> 'a list -> bool

Tests whether a predicate holds throughout a list.

all P [x1,...,xn] equals P x1 andalso .... andalso P xn. all P [] yields true.

Failure

If P x0,...,P x(j-1) all evaluate to true and P xj raises an exception e, then all P [x0,...,x(j-1),xj,...,xn] raises e.

Example

- all (equal 3) [3,3,3];
> val it = true : bool

- all (equal 3) [];
> val it = true : bool

- all (fn _ => raise Fail "") [];
> val it = true : bool

- all (fn _ => raise Fail "") [1];
! Uncaught exception:
! Fail  ""

See also

Lib.all2, Lib.exists, Lib.first