Arraylib updated

[Richard Russell]

I've updated the arraylib library to include the following new procedure, which creates a one-dimensional numeric array (of any type) aliasing a block of memory:

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      PROC_arrayalias(a(), p%%, N%)

On return the array a() will point to the block of memory starting at address p%% with length N% elements (so for example in the case of an integer array the size of the memory block would be N% * 4 bytes).

You can use this procedure to create two arrays which reference the same memory, for example:

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      DIM one%(9)
      PROC_arrayalias(two&(), ^one%(0), 40)

Now one%() and two&() reference the same 40 bytes of data.

You can also use it to alias an array in a structure, useful if you want to apply one of the whole array operations to it, which you usually can't do:

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      DIM struct{array%(4)}
      PROC_arrayalias(temp%(), ^struct.array%(0), 5)
      PRINT SUM(temp%())

As a new release of BBC BASIC for SDL 2.0 in unlikely in the foreseeable future you can grab a copy of the library directly from GitHub.