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User-defined
types
You saw that you can declare variables of different types, like Integer, Long, String, etc...
User-defined types allows you to group variables
together. You will sometimes have to group several
variables in one to define something very special.
Each variable in this group (called "field")
will represents a property of this entity.
Declaration of a new type:
To declare a new type, here is the syntax :
Type TypeName
'fields...
EndType
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In the 'fields..., you must put the fields of the type.
For example, if you create a type to describe somebody, you can take severals things like name, age, phone number. The declaration will look like this :
Type Person
Name as String
Age as Integer
Phone as Long
EndType
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Variable declaration :
Local VariableName as TypeName
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or
Public VariableName as TypeName
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To declare a variable of a type you defined, it is the same syntax. For our example of Person type, we would declare variables like this :
So, you can use the fields of the variable Marc :
Marc.Name = "Marc Smith"
Marc.Age = 34
Marc.Phone = 98324348532
'...
'birthday !
Marc.Age = Marc.Age + 1
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A bit futher, use of arguments :
You can also use user-defined types for arguments
of functions and procedures. The syntax is the same
as for classic variables. Following example shows
the use of a type defined by the programmer during
a function call :
Procedure DisplayName : (a as Person)
Locate 2,2, a.Name , 4
'...instructions
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