This is a simple integer scalar.  It identifies the total available space in the active workspace area given as the number of bytes it could hold.

A side effect of using ⎕WA is an internal reorganisation of the workspace and process memory, as follows:

1. Any un-referenced memory is discarded. This process, known as garbage collection, is required because whole cycles of refs can become un-referenced.
2. Numeric arrays are demoted to their tightest form. For example, a simple numeric array that happens to contain only values 0 or 1, is demoted or squeezed to have a ⎕DR type of 11 (Boolean).
3. All remaining used memory blocks are copied to the low-address end of the workspace, leaving a single free block at the high-address end. This process is known as compaction.
4. All memory allocated is returned to the Operating System except the space required for the compacted workspace, plus a working overhead based on the configured maximum workspace size (MAXWS). If the compacted workspace occupies more than 1/16 of MAXWS then the overhead is 1/16 of MAXWS, otherwise it is 1/64 of MAXWS. On a Windows system, you can see the process size changing by using Task Manager.

      ⎕WA
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