Node:Sequencing, Next:, Previous:Binding constructs, Up:Derived expression types


Sequencing

begin <expression1> <expression2> ... library syntax

The <expression>s are evaluated sequentially from left to right, and the value(s) of the last <expression> is(are) returned. This expression type is used to sequence side effects such as input and output. 

(define x 0)

(begin (set! x 5)
       (+ x 1))                        ==>  6

(begin (display "4 plus 1 equals ")
       (display (+ 4 1)))              ==>  unspecified
          and prints  4 plus 1 equals 5