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Bots / The Ultimate Palm Robot/ Mukhar & Johnson / 222880-6 / Chapter 6

136 The Ultimate Palm Robot

Want an example? If you have a variable (let’s call it x), you can test it for
various conditions. The program might need to make a decision based on cri-
teria: if x is greater than some value (x > 5), less than some value (x < 10), or
equal to some value (x == 13), for instance. Using the and or or operators, you
can further test for multiple conditions. For example, you can test if x lies be-
tween two values (the condition x>5&&x<10 is read as “x greater than 5 and
x less than 10.” It is true if x is between 5 and 10); or whether x meets any one
of several conditions (the condition x==2||x==4 is read as “x equals 2 or x
equals 4” and means the condition is true if either x equals 2 or x equals 4).

In addition to the If component, the Else component is used when you want
some code to execute when the condition is false. The Else block must be
added somewhere between the If and EndIf blocks. When you add an Else
block, the PRP automatically adds an EndElse block. Every program compo-
nent between Else and EndElse will be executed if the condition property of
the If block is false.

NOTE: The PRP will not stop you from adding an Else block anywhere
within a program. However, if you place an Else block where it is not between
an If and End If block, your program will not work.
The While Component A While component allows you to perform a loop
until some condition is met. The single property for the While component is
the condition. This condition meets the same parameters as the condition for
the If component. When you add a While block to your program, the PRP
automatically adds an EndWhile block. You can add components between the
While and EndWhile blocks. When the While component is encountered, the
condition is tested. If the condition is true, the components between the While
and EndWhile blocks are executed. The program then goes back to the start of
the While component. If the condition is false, the program goes to the next
component after the EndWhile component; if true, it executes the
components contained in the While component again.

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