Groovy: List: inject: Perform reduce operation

public Object inject(Closure closure)

public Object inject(Object initialValue, Closure closure)

Above functions perform the reduction operation. First overloaded form of the function takes head of the collection as initial value.

HelloWorld.groovy

result1 = [ 1, 2, 3, 4].inject { acc, val -> acc * val }
result2 = [ 1, 2, 3, 4].inject { acc, val -> acc + val }

result3 = [ 1, 2, 3, 4].inject(100) { acc, val -> acc * val }
result4 = [1, 2, 3, 4].inject('Appending -> ') { str, item -> str + item }

println "result1 : $result1"
println "result2 : $result2"
println "result3 : $result3"
println "result4 : $result4"

Output

result1 : 24

result2 : 10

result3 : 2400

result4 : Appending: 1234

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