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72 lines
2.1 KiB
Plaintext
72 lines
2.1 KiB
Plaintext
{{DISPLAYTITLE:_MEM (function)}}
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The [[_MEM]] function returns a _MEM block referring to the largest possible continuous memory region beginning at a variable's offset.
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{{PageSyntax}}
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: {{Parameter|memoryBlock}} = [[_MEM]]({{Parameter|referenceVariable}})
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===Unsecure syntax===
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: {{Parameter|memoryBlock}} = [[_MEM]]({{Parameter|offset}}, {{Parameter|byteSize}})
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{{Parameters}}
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* The {{Parameter|memoryBlock}} created will hold the {{Parameter|referenceVariable}} or [[arrays|array]] value(s), type and byte size in a separate memory area.
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* The secure syntax {{Parameter|referenceVariable}} is an existing variable's referenced memory block.
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* The unsecure syntax's designated {{Parameter|offset}} and {{Parameter|byteSize}} cannot be guaranteed. '''Avoid if possible.'''
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{{PageDescription}}
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* The {{Parameter|memoryBlock}} [[_MEM]] type variable holds the following read-only elements: OFFSET, SIZE, TYPE and ELEMENTSIZE.
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* All values created by memory functions MUST be freed using [[_MEMFREE]] with a valid [[_MEM]] variable type.
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* '''_MEM function cannot reference variable length [[STRING]] variable values. String values must be designated as a fixed-[[LEN|length]] string.'''
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{{PageExamples}}
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''Example:'' Assigning values to reference variables in memory.
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{{CodeStart}} '' ''
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{{Cl|DIM}} {{Cl|SHARED}} m(3) {{Cl|AS}} {{Cl|_MEM}}
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{{Cl|DIM}} {{Cl|SHARED}} Saved(3)
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m(1) = {{Cl|_MEM (function)|_MEM}}(x)
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m(2) = {{Cl|_MEM (function)|_MEM}}(y)
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m(3) = {{Cl|_MEM (function)|_MEM}}(z)
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x = 3: y = 5: z = 8
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{{Cl|PRINT}} x, y, z
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Save x, y, z
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x = 30: y = 50: z = 80
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{{Cl|PRINT}} x, y, z
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RestoreIt
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{{Cl|PRINT}} x, y, z
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{{Cl|_MEMFREE}} m(1)
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{{Cl|_MEMFREE}} m(2)
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{{Cl|_MEMFREE}} m(3)
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{{Cl|END}}
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{{Cl|SUB}} Save (n1, n2, n3)
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Saved(1) = n1
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Saved(2) = n2
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Saved(3) = n3
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{{Cl|END SUB}}
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{{Cl|SUB}} RestoreIt
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{{Cl|_MEMPUT}} m(1), m(1).OFFSET, Saved(1)
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{{Cl|_MEMPUT}} m(2), m(2).OFFSET, Saved(2)
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{{Cl|_MEMPUT}} m(3), m(3).OFFSET, Saved(3)
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{{Cl|END SUB}} '' ''
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{{CodeEnd}}{{small|Code by SMcNeill}}
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{{PageSeeAlso}}
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* [[_MEM]] {{text|(variable type)}}
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* [[_MEMNEW]], [[_MEMCOPY]]
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* [[_MEMGET]], [[_MEMPUT]]
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* [[_MEMFILL]], [[_MEMIMAGE]]
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* [[_MEMFREE]]
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{{PageNavigation}}
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