# delay

`(delay EXPRESSION)`
A 'delay' expression contains a single subexpression. The subexpression is not evaluated until the delay is `force`d. Then, when `force` is applied to the result of the delay expression, the subexpression is evaluated and the result of the subexpression is the result of the force. If the same delayed expression is forced a second time, the result of the first force is used again, the subexpression is only evaluated once.

Advanced Student Table of Contents