Most of the programs you have seen so far have asked Vision to perform a single request. There are situations where you would like to perform a set of operations, one after another. Vision provides a simple mechanism for accomplishing this. Each expression in a program is known as a Statement . Each statement is executed in sequence.
Programs always return the value of the last statement executed.
This value is automatically printed by Vision. The final statement prints the sum followed by a carriage return. Some expressions that can be written as a single expression, can be subdivided into more manageable pieces by creating multiple expressions. A Block is a program that represents a deferred sequence of actions. Syntactically, a block is a program surrounded by square brackets.