Flowdock
method

with_index

Importance_2
Ruby latest stable (v1_9_3_392) - 2 notes - Class: Enumerator
with_index(p1 = v1) public

Iterates the given block for each element with an index, which starts from offset. If no block is given, returns a new Enumerator that includes the index, starting from offset

offset

the starting index to use

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February 2, 2013 - (v1_9_3_125)
1 thank

Enumerator#with_index has confusing documentation

Enumerator#with_index has confusing documentation, but hopefully this will make it clearer.

Code example

a=[11,22,31,224,44].to_enum
=> [11, 22, 31, 224, 44]
a.with_index { |val,index| puts "index: #{index} for #{val}" }
index: 0 for 11
index: 1 for 22
index: 2 for 31
index: 3 for 224
index: 4 for 44

a=[11,22,31,224,44].to_enum
=> #<Enumerator: [11, 22, 31, 224, 44]:each>
a.with_index(2){ |val,index| puts "index: #{index} for #{val}" if val > 30 }
index: 4 for 31
index: 5 for 224
index: 6 for 44
=> [11, 22, 31, 224, 44
March 5, 2013
0 thanks

Minor correction to Rubybull's examples?

Was your first example intended to be:

a=[11,22,31,224,44]
=> [11, 22, 31, 224, 44]
a.each.with_index { |val,index| puts "index: #{index} for #{val}" }