20 lines
487 B
Erlang
20 lines
487 B
Erlang
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%% A process whose only job is to keep a counter.
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%% First version
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-module(counter).
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-export([start/0, codeswitch/1]).
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start() -> loop(0).
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loop(Sum) ->
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receive
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{increment, Count} ->
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loop(Sum+Count);
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{counter, Pid} ->
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Pid ! {counter, Sum},
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loop(Sum);
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code_switch ->
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?MODULE:codeswitch(Sum)
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% Force the use of 'codeswitch/1' from the latest MODULE version
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end.
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codeswitch(Sum) -> loop(Sum).
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