Software Customisation Guide
Variables, Objects, Functions and Methods
Variables, Objects, Functions and Methods
PML Variables
Variables are used to store values. Variables have names. The value that is stored can be changed but the name is fixed. The user chooses the names and decides what is stored by each variable.
The variables used in PML 2 are objects:
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Every object (variable) has a unique name.
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An object has a set of functions associated with it, which can be called to manipulate this data. These functions are called methods.
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Some methods change the data held by the object, some return a result derived from the data, and some methods do both.
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The data that an object can hold and the functions that are available are fixed by the object type (sometimes called the object’s class).
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Before the user can create an object, the object type must have been defined. The object type definition specifies what the members and methods are for that type of object.
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