_MEMELEMENT

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The _MEMELEMENT function returns a _MEM block referring to a variable's memory, but not past it.


Syntax

memoryBlock = _MEMELEMENT(referenceVariable)


  • The referenceVariable parameter designates the existing variable name using the memory block.
  • _MEMELEMENT is the same as _MEM but in an array it returns the specifications of an element, not the entire array.
  • All values created by memory functions MUST be freed using _MEMFREE with a valid _MEM variable type.
  • The _MEMELEMENT type contains the following read-only elements where name is the variable name:
name.OFFSET is the beginning offset of the memory block AS _OFFSET
name.SIZE returns the largest available region of memory of the ELEMENT in bytes AS _OFFSET
name.ELEMENTSIZE is the _BYTE size of the elements within the block AS _OFFSET
  • 2 = INTEGER values have an element size of 2 bytes
  • 4 = LONG integer and SINGLE float values have an element size of 4 bytes
  • 8 = DOUBLE float and _INTEGER64 values have an element size of 8 bytes
  • 32 = _FLOAT values have an element size of 32 bytes
  • LEN = STRING or _OFFSET byte sizes vary so use LEN(variable) for the number of bytes.
name.TYPE is the type (represented as bits combined to form a value) AS LONG (see below).

.TYPE values (version 1.000 and up)

  • 0 = UDT (user defined type) or memory created by _MEMNEW
  • 1 = 1 bit ELEMENT.SIZE=1 *Only used along with specific types (currently integers or floats)
  • 2 = 2 bit. ELEMENT.SIZE=2 *
  • 4 = 4 bit. ELEMENT.SIZE=4 *
  • 8 = 8 bit. ELEMENT.SIZE=8 *
  • 16 = 16 bit. ELEMENT.SIZE=16 *
  • 32 = 32 bit. ELEMENT.SIZE=32 *
  • 64 = 64 bit. ELEMENT.SIZE=64 *
  • 128 = 128 bit. ELEMENT.SIZE=128 *
  • 256 = 256 bit. ELEMENT.SIZE=256 *
  • 512(+ bit*) = integer types only(ie. whole numbers)
  • 1024(+ bit*) = floating point types only(ie. numbers that can have a decimal point)
  • 2048 = STRING type only
  • 4096(+ 512 + bit*) = _UNSIGNED integer type only
  • 8192 = _MEM type only
  • 16384(+ 512 + bit*)= _OFFSET type only

Note: If a future integer, float or other type doesn't have a size that is 1,2,4,8,16,32,64,128 or 256 it won't have a size-bit set.

Versions prior to 1.000

Note: _MEM and _OFFSET values cannot be cast to other variable types.


Examples

Example: Comparing the specifications returned by _MEM and _MEMELEMENT from an array.

DIM a(1 TO 100) AS _UNSIGNED _BYTE DIM m1 AS _MEM DIM m2 AS _MEM m1 = _MEM(a(50)) 'function returns information about array up to specific element PRINT m1.OFFSET, m1.SIZE, m1.TYPE, m1.ELEMENTSIZE m2 = _MEMELEMENT(a(50)) 'function returns information about the specific element PRINT m2.OFFSET, m2.SIZE, m2.TYPE, m2.ELEMENTSIZE END

Output using VERSION .954 ONLY .TYPE values: 1 (integer) + 2 (unsigned)

28377205 51 3 1 28377205 1 3 1

Explanation: _MEM returns the info about the array to that element while _MEMELEMENT returns info about that element only.
  • _MEM value returns the available array .SIZE as 51 bytes from the designated array element.
  • _MEMELEMENT value returns the available element .SIZE as one byte.


See also



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