Spawn

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Revision as of 01:23, 7 August 2022 by Brian E (talk | contribs) (Created page with "{| class=vertical-navbox style="float:right; font-size:500%; margin:0 1ex;" |<code>&</code> |} == Spawn == ==== {R}←{X}f&Y ==== & is a monadic operator with an ambivalent...")
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&

Spawn

{R}←{X}f&Y

& is a monadic operator with an ambivalent derived function. & spawns a new thread in which f is applied to its argument Y (monadic case) or between its arguments X and Y (dyadic case). The shy result of this application is the number of the newly created thread.

When function f terminates, its result (if any), the thread result, is returned.

⎕TSYNC, used monadically, given the thread number can be used to wait for a result from that thread. If no ⎕TSYNC is in effect, the thread result is displayed in the session in the normal fashion.


Note that & can be used in conjunction with the each operator ¨ to launch many threads in parallel.

Examples

      ÷&4         ⍝ Reciprocal in background
0.25
      ÷&4       ⍝ Show thread number
1
0.25
 
      FOO&88      ⍝ Spawn monadic function.
 
      2 FOO&3     ⍝ dyadic
 
      {NIL}&0     ⍝ niladic
 
      &'NIL'     ⍝ ..
 
      X.GOO&99    ⍝ thread in remote space.
 
      &'⎕dl 2'   ⍝ Execute async expression.
 
      'NS'&'FOO' ⍝ .. remote .. .. .. 
 
      PRT⎕nl 9 ⍝ PRT spaces in parallel.