Vocabulary
kernel.private

Inputs and outputs

spec	an array of class words

Word description
Declares that the elements at the top of the stack are instances of the classes in spec.



Examples
The optimizer cannot do anything with the below code:

2 + 10 *

However, if we declare that the top of the stack is a float, then type checks and generic dispatch are eliminated, and the compiler can use unsafe intrinsics:

{ float } declare 2 + 10 *

Definition

USING: kernel ;

IN: kernel.private

: declare ( spec -- ) drop ;