cheat sheets.

Cheat Sheet Title: [ no_spaces_alphanumeric_only ]

Cheat Sheet:
Ruby Enumerable Mixin (* require 'enumerator') all? {|obj| } Returns true if EVERY obj returns true from block any? {|obj| } Returns true if ANY obj returns true from block collect {|obj| } Alias for map detect(ifnone=nil) {|obj| } alias for find * each_cons(n) {} Iterates over arrays of n consecutive elements (overlap) * each_slice(n) {} Iterates over slices of n elements (no overlap) each_with_index {|obj, index| ... } entries Returns an Array of all objects, alias for to_a * enum_cons(n) Enumerable::Enumerator.new(self, :each_cons, n) * enum_slice(n) Enumerable::Enumerator.new(self, :each_slice, n) * enum_with_index Enumerable::Enumerator.new(self, :each_with_index) find(ifnone=nil) {|obj| } Returns first obj for which block is true find_all {|obj|} Returns an Array of all objects for which block is true grep(pattern) {} Returns an Array of / iterates over objects that === pattern include?(obj) True if any member == obj inject(initial) {|mem, obj| } Runs block on each obj, with last result in mem inject {|mem, obj| } Like above but first element used for initial map {|obj| } Returns new array with results of running block on each max Returns largest element; elements must be Comparable max {|a,b| } Returns largest element; block should return a <=> b member? Alias for include? min Like max but returns smallest partition {|obj|} Returns [[objects block was true], [objects it was false]] reject {|obj| } Returns array of elements for which block was false select Alias for find_all sort Returns array of elements sorted; elements must be Comparable sort {|a,b| } Returns elements sorted, block should return a <=> b sort_by {|obj| } Returns elements sorted according to keys produced by block to_a Returns an Array of all objects, alias for entries to_set Creates a Set from elements, must require "set" zip(args, ...) Merges elements with corresponding elements from each arg

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