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## 3.E. Variable Declaration Part 

Every variable identifier occurring in a program must be introduced in a variable declaration. This declaration must textually precede any use of the variable, unless the variable is a program parameter. 

A variable declaration introduces a variable identifier and its associated data type by simply listing the identifier followed by the type. The symbol var heads the variable declaration part. The general form is: 

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Example: 

var Rootl, Root2, Root3: Real: Count, I: Integer; Found: Boolean; Filler: Char; 

Any identifier (denoting an external entity - usually a file) listed in the program heading parameter list except Input or Output must be declared in the program's variable declaration part. Input or Output, if listed, are automatically declared to be textfiles (see Chapter 9). 

program TemperatureConversion(Output); { Program 3.1 - Example program illustrating constant and type definition and variable declaration parts. } const Bias = 32; Factor = 1.8; Low Separator = ' '; Blanks type CelciusRange = Low .. High -20; High , . $_{, }$ 39; { a subrange type-see Chapter 5 }; 

