org.codehaus.groovy.runtime
[Java] Class ComposedClosure

java.lang.Object
  groovy.lang.GroovyObjectSupport
      groovy.lang.Closure
          org.codehaus.groovy.runtime.ComposedClosure

public final class ComposedClosure
extends Closure

A wrapper for Closure to support composition. Normally used only internally through the rightShift() and leftShift() methods on Closure.

Typical usages:

 def twice = { a -> a * 2 }
 def inc = { b -> b + 1 }
 def f = { x -> twice(inc(x)) } // longhand
 def g = inc >> twice
 def h = twice << inc
 assert f(10) == 22
 assert g(10) == 22
 assert h(10) == 22

 def s2c = { it.chars[0] }
 def p = Integer.&toHexString >> s2c >> Character.&toUpperCase
 assert p(15) == 'F'

 def multiply = { a, b -> a * b }
 def identity = { a -> [a, a] }
 def sq = identity >> multiply
 assert (1..5).collect{ sq(it) } == [1, 4, 9, 16, 25]

 def add3 = { a, b, c -> a + b + c }
 def add2plus10 = add3.curry(10)
 def multBoth = { a, b, c -> [a*c, b*c] }
 def twiceBoth = multBoth.rcurry(2)
 def twiceBothPlus10 = twiceBoth >> add2plus10
 assert twiceBothPlus10(5, 10) == 40
 

Authors:

Paul King

ComposedClosure

public ComposedClosure(Closure first, Closure second)

call

@Override
public Object call(Object... args)

clone

public Object clone()

doCall

public Object doCall(Object... args)

getDelegate

public Object getDelegate()

getParameterTypes

public Class[] getParameterTypes()

getResolveStrategy

public int getResolveStrategy()

setDelegate

public void setDelegate(Object delegate)

setResolveStrategy

public void setResolveStrategy(int resolveStrategy)

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