rsc3/doc-schelp/HelpSource/Classes/Pcollect.schelp

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class:: Pcollect
summary:: Apply a function to a pattern
categories:: Streams-Patterns-Events>Patterns>Filter
related:: Classes/Pselect, Classes/Preject
description::
Modifies each value by passing it to the function.
classmethods::
method:: new
argument:: func
A link::Classes/Function::. Receives values from code::pattern::.
argument:: pattern
A link::Classes/Pattern::.
examples::
code::
(
a = Pcollect( { |item| item * 3 }, Pseq( #[ 1, 2, 3 ], inf ) );
x = a.asStream;
9.do( { x.next.postln; } );
)
::
The message code::collect:: returns a Pcollect when passed to a pattern. Note that because the pattern is converted to a link::Classes/Stream:: (more precisely a link::Classes/FuncStream::) the collect function is evaluated for one item each time the message code::next:: is passed.
code::
(
a = Pseq( #[ 1, 2, 3 ], inf ).collect( { arg item; item * 3 } );
a.postln;
x = a.asStream;
9.do( { x.next.postln; } );
)
::