43 lines
1.2 KiB
ObjectPascal
43 lines
1.2 KiB
ObjectPascal
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program pointerDemo;
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type
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{
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A new pointer data type is declared by `↑` followed by a data type name,
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the domain.
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The domain data type may not have been declared yet, but must be
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declared within the current `type` section.
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Most compilers do not support the reference token `↑` as specified in
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the ISO standards 7185 and 10206, but use the alternative `^` (caret).
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}
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integerReference = ^integer;
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var
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integerLocation: integerReference;
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begin
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{
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The procedure `new` taken one pointer variable and allocates memory for
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one new instance of the pointer domain’s data type (here an `integer`).
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The pointer variable will hold the address of the allocated instance.
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}
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new(integerLocation);
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{
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Dereferencing a pointer is done via appending `↑` to the variable’s
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name. All operations on the domain type are now possible.
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}
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integerLocation^ := 42;
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{
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The procedure `dispose` takes one pointer variable and releases the
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underlying memory. The supplied variable is otherwise not modified.
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}
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dispose(integerLocation);
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{
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In Pascal, `dispose` is not necessary. Any excess memory is automatically
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released after `program` termination.
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}
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end.
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