detect.rb

# frozen_string_literal: true

require 'flor/pcore/iterator'


class Flor::Pro::Detect < Flor::Macro::Iterator
  #
  # Detect is a simplified version of [find](find.md).
  #
  # ```
  # detect [ 1, 2, 3 ]
  #   (elt % 2) == 0
  # # f.ret --> 2
  # ```
  #
  # With objects (maps), it returns the first matching entry (pair).
  # ```
  # detect { a: 'A', b: 'B', c: 'C' }
  #   val == 'B'
  # # f.ret --> [ 'b', 'B' ]
  # ```
  #
  # ## iterating blocks
  #
  # Iterating blocks are given 3 to 4 local variables.
  #
  # A block iterating over an array will receive `elt` (the current element
  # of the iteration), `idx` (the zero-based index of the current element),
  # and `len` (the length of the array).
  #
  # A block iterating over an object will receive `key` (the current string
  # key), `val` (the current value), `idx` (the zero-based index of the
  # current key/val), and `len` (the length of the object).
  #
  # ## see also
  #
  # find.

  name 'detect'

  def rewrite_tree

    rewrite_iterator_tree('find')
  end
end