Pkey simplifies backward access to values in an event being processed by Pbind or another event pattern.
| key |
The name of the event variable to read from. |
| repeats |
The number of items returned before finishing. Using |
// \b should thus take twice the value of \a in each event:p = Pbind(\a, Pwhite(1, 10, inf), \b, Pkey(\a) * 2).asStream;p.next(()) // for Pbind, must pass in a default event even if empty( 'a': 10, 'b': 20 )( 'a': 2, 'b': 4 )( 'a': 5, 'b': 10 )( 'a': 4, 'b': 8 )( 'a': 2, 'b': 4 )// note: to check if a Pkey's result /equals/ another value,// be sure to use |==|p = Pbind( \a, Pseries(1, 1, inf), \b, Pif( Pkey(\a) == 2, "equals 2", "nope" )).asStream;p.next(()); // 'b' is always "nope"p = Pbind( \a, Pseries(1, 1, inf), \b, Pif( Pkey(\a) |==| 2, "equals 2", "nope" )).asStream;p.next(()); // 'b' is as expected