32 lines
679 B
Text
32 lines
679 B
Text
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class:: Pkey
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summary:: access a key in an event stream
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related:: Classes/Penvir
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categories:: Streams-Patterns-Events>Patterns>Data Sharing
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description::
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Pkey simplifies backward access to values in an event being processed by link::Classes/Pbind:: or another event pattern.
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ClassMethods::
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method::new
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argument::key
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The name of the event variable to read from.
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Examples::
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code::
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// \b should thus take twice the value of \a in each event:
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p = Pbind(\a, Pwhite(1, 10, inf), \b, Pkey(\a) * 2).asStream;
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p.next(()) // for Pbind, must pass in a default event even if empty
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( 'a': 10, 'b': 20 )
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( 'a': 2, 'b': 4 )
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( 'a': 5, 'b': 10 )
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( 'a': 4, 'b': 8 )
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( 'a': 2, 'b': 4 )
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::
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