mirror of
https://github.com/mruby/mruby
synced 2026-06-08 16:11:16 +00:00
dearblue
98d763603c
Replace `__product_group` method with `__product_generate` and `__product_next`. This change eliminates the need for Ruby to perform internal state calculations, allowing it to simply receive the results.
763 lines
21 KiB
Ruby
763 lines
21 KiB
Ruby
class Array
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##
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# call-seq:
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# ary.uniq! -> ary or nil
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# ary.uniq! { |item| ... } -> ary or nil
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#
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# Removes duplicate elements from `self`.
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# Returns `nil` if no changes are made (that is, no
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# duplicates are found).
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#
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# a = [ "a", "a", "b", "b", "c" ]
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# a.uniq! #=> ["a", "b", "c"]
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# b = [ "a", "b", "c" ]
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# b.uniq! #=> nil
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# c = [["student","sam"], ["student","george"], ["teacher","matz"]]
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# c.uniq! { |s| s.first } # => [["student", "sam"], ["teacher", "matz"]]
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#
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def uniq!(&block)
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if block
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hash = {}
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result = []
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self.each do |val|
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key = block.call(val)
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unless hash.key?(key)
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hash[key] = true
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result << val
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end
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end
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if result.size == self.size
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nil
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else
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self.replace(result)
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end
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else
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__uniq!
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end
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end
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##
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# call-seq:
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# ary.uniq -> new_ary
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# ary.uniq { |item| ... } -> new_ary
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#
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# Returns a new array by removing duplicate values in `self`.
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#
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# a = [ "a", "a", "b", "b", "c" ]
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# a.uniq #=> ["a", "b", "c"]
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#
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# b = [["student","sam"], ["student","george"], ["teacher","matz"]]
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# b.uniq { |s| s.first } # => [["student", "sam"], ["teacher", "matz"]]
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#
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def uniq(&block)
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if block
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ary = self.dup
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ary.uniq!(&block)
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ary
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else
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__uniq
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end
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end
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# for efficiency
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def reverse_each(&block)
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return to_enum(:reverse_each) unless block
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i = self.size - 1
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while i>=0
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block.call(self[i])
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i -= 1
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end
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self
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end
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##
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# call-seq:
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# ary.fetch(index) -> obj
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# ary.fetch(index, default) -> obj
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# ary.fetch(index) { |index| block } -> obj
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#
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# Tries to return the element at position `index`, but throws an IndexError
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# exception if the referenced `index` lies outside of the array bounds. This
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# error can be prevented by supplying a second argument, which will act as a
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# `default` value.
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#
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# Alternatively, if a block is given it will only be executed when an
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# invalid `index` is referenced.
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#
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# Negative values of `index` count from the end of the array.
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#
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# a = [ 11, 22, 33, 44 ]
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# a.fetch(1) #=> 22
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# a.fetch(-1) #=> 44
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# a.fetch(4, 'cat') #=> "cat"
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# a.fetch(100) { |i| puts "#{i} is out of bounds" }
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# #=> "100 is out of bounds"
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#
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def fetch(n, ifnone=NONE, &block)
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#warn "block supersedes default value argument" if !n.nil? && ifnone != NONE && block
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if block
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# Block case: use shared index helper + Ruby block handling
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normalized_index = __normalize_index(n)
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if normalized_index
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self[normalized_index]
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else
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block.call(n)
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end
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else
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# Fast C implementation for non-block cases
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__fetch(n, ifnone, NONE)
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end
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end
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##
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# call-seq:
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# ary.fill(obj) -> ary
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# ary.fill(obj, start [, length]) -> ary
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# ary.fill(obj, range ) -> ary
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# ary.fill { |index| block } -> ary
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# ary.fill(start [, length] ) { |index| block } -> ary
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# ary.fill(range) { |index| block } -> ary
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#
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# The first three forms set the selected elements of `self` (which
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# may be the entire array) to `obj`.
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#
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# A `start` of `nil` is equivalent to zero.
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#
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# A `length` of `nil` is equivalent to the length of the array.
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#
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# The last three forms fill the array with the value of the given block,
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# which is passed the absolute index of each element to be filled.
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#
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# Negative values of `start` count from the end of the array, where +-1+ is
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# the last element.
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#
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# a = [ "a", "b", "c", "d" ]
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# a.fill("x") #=> ["x", "x", "x", "x"]
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# a.fill("w", -1) #=> ["x", "x", "x", "w"]
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# a.fill("z", 2, 2) #=> ["x", "x", "z", "z"]
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# a.fill("y", 0..1) #=> ["y", "y", "z", "z"]
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# a.fill { |i| i*i } #=> [0, 1, 4, 9]
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# a.fill(-2) { |i| i*i*i } #=> [0, 1, 8, 27]
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# a.fill(1, 2) { |i| i+1 } #=> [0, 2, 3, 27]
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# a.fill(0..1) { |i| i+1 } #=> [1, 2, 3, 27]
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#
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def fill(arg0=nil, arg1=nil, arg2=nil, &block)
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if arg0.nil? && arg1.nil? && arg2.nil? && !block
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raise ArgumentError, "wrong number of arguments (given 0, expected 1..3)"
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end
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# Use shared C argument parser for all cases
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start, length = __fill_parse_arg(arg0, arg1, arg2, &block)
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if block
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# Block-based filling in Ruby
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i = start
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while i < start + length
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self[i] = block.call(i)
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i += 1
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end
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else
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# Use fast C implementation for value filling
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__fill_exec(start, length, arg0)
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end
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self
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end
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##
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# call-seq:
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# ary.delete_if { |item| block } -> ary
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# ary.delete_if -> Enumerator
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#
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# Deletes every element of `self` for which block evaluates to `true`.
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#
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# The array is changed instantly every time the block is called, not after
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# the iteration is over.
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#
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# See also Array#reject!
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#
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# If no block is given, an Enumerator is returned instead.
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#
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# scores = [ 97, 42, 75 ]
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# scores.delete_if {|score| score < 80 } #=> [97]
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def delete_if(&block)
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return to_enum(:delete_if) unless block
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result = []
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idx = 0
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len = size
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while idx < len
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elem = self[idx]
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result << elem unless block.call(elem)
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idx += 1
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end
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self.replace(result)
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end
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##
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# call-seq:
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# ary.reject! { |item| block } -> ary or nil
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# ary.reject! -> Enumerator
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#
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# Equivalent to Array#delete_if, deleting elements from `self` for which the
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# block evaluates to `true`, but returns `nil` if no changes were made.
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#
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# The array is changed instantly every time the block is called, not after
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# the iteration is over.
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#
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# See also Enumerable#reject and Array#delete_if.
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#
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# If no block is given, an Enumerator is returned instead.
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def reject!(&block)
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return to_enum(:reject!) unless block
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result = []
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idx = 0
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len = size
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while idx < len
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elem = self[idx]
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result << elem unless block.call(elem)
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idx += 1
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end
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return nil if len == result.size
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self.replace(result)
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end
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##
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# call-seq:
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# ary.bsearch {|x| block } -> elem
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#
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# By using binary search, finds a value from this array which meets
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# the given condition in O(log n) where n is the size of the array.
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#
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# You can use this method in two use cases: a find-minimum mode and
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# a find-any mode. In either case, the elements of the array must be
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# monotone (or sorted) with respect to the block.
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#
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# In find-minimum mode (this is a good choice for typical use case),
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# the block must return true or false, and there must be an index i
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# (0 <= i <= ary.size) so that:
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#
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# - the block returns false for any element whose index is less than
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# i, and
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# - the block returns true for any element whose index is greater
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# than or equal to i.
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#
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# This method returns the i-th element. If i is equal to ary.size,
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# it returns nil.
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#
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# ary = [0, 4, 7, 10, 12]
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# ary.bsearch {|x| x >= 4 } #=> 4
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# ary.bsearch {|x| x >= 6 } #=> 7
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# ary.bsearch {|x| x >= -1 } #=> 0
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# ary.bsearch {|x| x >= 100 } #=> nil
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#
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# In find-any mode (this behaves like libc's bsearch(3)), the block
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# must return a number, and there must be two indices i and j
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# (0 <= i <= j <= ary.size) so that:
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#
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# - the block returns a positive number for ary[k] if 0 <= k < i,
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# - the block returns zero for ary[k] if i <= k < j, and
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# - the block returns a negative number for ary[k] if
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# j <= k < ary.size.
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#
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# Under this condition, this method returns any element whose index
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# is within i...j. If i is equal to j (i.e., there is no element
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# that satisfies the block), this method returns nil.
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#
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# ary = [0, 4, 7, 10, 12]
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# # try to find v such that 4 <= v < 8
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# ary.bsearch {|x| 1 - (x / 4).truncate } #=> 4 or 7
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# # try to find v such that 8 <= v < 10
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# ary.bsearch {|x| 4 - (x / 2).truncate } #=> nil
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#
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# You must not mix the two modes at a time; the block must always
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# return either true/false, or always return a number. It is
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# undefined which value is actually picked up at each iteration.
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def bsearch(&block)
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return to_enum(:bsearch) unless block
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if idx = bsearch_index(&block)
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self[idx]
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else
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nil
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end
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end
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##
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# call-seq:
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# ary.bsearch_index {|x| block } -> int or nil
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#
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# By using binary search, finds an index of a value from this array which
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# meets the given condition in O(log n) where n is the size of the array.
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#
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# It supports two modes, depending on the nature of the block and they are
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# exactly the same as in the case of #bsearch method with the only difference
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# being that this method returns the index of the element instead of the
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# element itself. For more details consult the documentation for #bsearch.
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def bsearch_index(&block)
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return to_enum(:bsearch_index) unless block
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low = 0
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high = size
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satisfied = false
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while low < high
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mid = ((low+high)/2).truncate
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res = block.call(self[mid])
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case res
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when 0 # find-any mode: Found!
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return mid
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when Numeric # find-any mode: Continue...
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in_lower_half = res < 0
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when true # find-min mode
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in_lower_half = true
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satisfied = true
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when false, nil # find-min mode
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in_lower_half = false
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else
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raise TypeError, 'invalid block result (must be numeric, true, false or nil)'
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end
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if in_lower_half
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high = mid
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else
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low = mid + 1
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end
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end
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satisfied ? low : nil
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end
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##
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# call-seq:
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# ary.keep_if { |item| block } -> ary
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# ary.keep_if -> Enumerator
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#
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# Deletes every element of `self` for which the given block evaluates to
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# `false`.
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#
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# See also Array#select!
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#
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# If no block is given, an Enumerator is returned instead.
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#
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# a = [1, 2, 3, 4, 5]
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# a.keep_if { |val| val > 3 } #=> [4, 5]
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def keep_if(&block)
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return to_enum(:keep_if) unless block
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result = []
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idx = 0
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len = size
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while idx < len
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elem = self[idx]
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result << elem if block.call(elem)
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idx += 1
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end
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self.replace(result)
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end
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##
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# call-seq:
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# ary.select! {|item| block } -> ary or nil
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# ary.select! -> Enumerator
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#
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# Invokes the given block passing in successive elements from `self`,
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# deleting elements for which the block returns a `false` value.
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#
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# If changes were made, it will return `self`, otherwise it returns `nil`.
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#
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# See also Array#keep_if
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#
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# If no block is given, an Enumerator is returned instead.
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def select!(&block)
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return to_enum(:select!) unless block
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result = []
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idx = 0
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len = size
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while idx < len
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elem = self[idx]
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result << elem if block.call(elem)
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idx += 1
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end
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return nil if len == result.size
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self.replace(result)
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end
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##
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# call-seq:
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# ary.dig(idx, ...) -> object
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#
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# Extracts the nested value specified by the sequence of *idx*
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# objects by calling `dig` at each step, returning `nil` if any
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# intermediate step is `nil`.
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#
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def dig(idx,*args)
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idx = idx.__to_int
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n = self[idx]
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if args.size > 0
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n&.dig(*args)
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else
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n
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end
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end
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##
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# call-seq:
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# ary.permutation { |p| block } -> ary
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# ary.permutation -> Enumerator
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# ary.permutation(n) { |p| block } -> ary
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# ary.permutation(n) -> Enumerator
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#
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# When invoked with a block, yield all permutations of length `n` of the
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# elements of the array, then return the array itself.
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#
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# If `n` is not specified, yield all permutations of all elements.
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#
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# The implementation makes no guarantees about the order in which the
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# permutations are yielded.
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#
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# If no block is given, an Enumerator is returned instead.
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#
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# Examples:
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#
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# a = [1, 2, 3]
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# a.permutation.to_a #=> [[1,2,3],[1,3,2],[2,1,3],[2,3,1],[3,1,2],[3,2,1]]
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# a.permutation(1).to_a #=> [[1],[2],[3]]
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# a.permutation(2).to_a #=> [[1,2],[1,3],[2,1],[2,3],[3,1],[3,2]]
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# a.permutation(3).to_a #=> [[1,2,3],[1,3,2],[2,1,3],[2,3,1],[3,1,2],[3,2,1]]
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# a.permutation(0).to_a #=> [[]] # one permutation of length 0
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# a.permutation(4).to_a #=> [] # no permutations of length 4
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def permutation(n=self.size, &block)
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n = n.__to_int
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return to_enum(:permutation, n) unless block
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size = self.size
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if n == 0
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yield []
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elsif 0 < n && n <= size
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i = 0
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while i<size
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result = [self[i]]
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if n-1 > 0
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ary = self[0...i] + self[i+1..-1]
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ary.permutation(n-1) do |c|
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yield result + c
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end
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else
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yield result
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end
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i += 1
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end
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end
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self
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end
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##
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# call-seq:
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# ary.combination(n) { |c| block } -> ary
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# ary.combination(n) -> Enumerator
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#
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# When invoked with a block, yields all combinations of length `n` of elements
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# from the array and then returns the array itself.
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#
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# The implementation makes no guarantees about the order in which the
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# combinations are yielded.
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#
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# If no block is given, an Enumerator is returned instead.
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#
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# Examples:
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#
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# a = [1, 2, 3, 4]
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# a.combination(1).to_a #=> [[1],[2],[3],[4]]
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# a.combination(2).to_a #=> [[1,2],[1,3],[1,4],[2,3],[2,4],[3,4]]
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# a.combination(3).to_a #=> [[1,2,3],[1,2,4],[1,3,4],[2,3,4]]
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# a.combination(4).to_a #=> [[1,2,3,4]]
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# a.combination(0).to_a #=> [[]] # one combination of length 0
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# a.combination(5).to_a #=> [] # no combinations of length 5
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def combination(n, &block)
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n = n.__to_int
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return to_enum(:combination, n) unless block
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size = self.size
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if n == 0
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yield []
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elsif n == 1
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i = 0
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while i<size
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yield [self[i]]
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i += 1
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end
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elsif n <= size
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i = 0
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while i<size
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result = [self[i]]
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self[i+1..-1].combination(n-1) do |c|
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yield result + c
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end
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i += 1
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end
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end
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self
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end
|
|
|
|
##
|
|
# call-seq:
|
|
# ary.transpose -> new_ary
|
|
#
|
|
# Assumes that self is an array of arrays and transposes the rows and columns.
|
|
#
|
|
# If the length of the subarrays don't match, an IndexError is raised.
|
|
#
|
|
# Examples:
|
|
#
|
|
# a = [[1,2], [3,4], [5,6]]
|
|
# a.transpose #=> [[1, 3, 5], [2, 4, 6]]
|
|
|
|
def transpose
|
|
return [] if empty?
|
|
|
|
column_count = nil
|
|
self.each do |row|
|
|
raise TypeError unless row.is_a?(Array)
|
|
column_count ||= row.size
|
|
raise IndexError, 'element size differs' unless column_count == row.size
|
|
end
|
|
|
|
Array.new(column_count) do |column_index|
|
|
self.map {|row| row[column_index] }
|
|
end
|
|
end
|
|
|
|
##
|
|
# call-seq:
|
|
# ary.to_h -> Hash
|
|
# ary.to_h{|item| ... } -> Hash
|
|
#
|
|
# Returns the result of interpreting *array* as an array of
|
|
# `[key, value]` pairs. If a block is given, it should
|
|
# return `[key, value]` pairs to construct a hash.
|
|
#
|
|
# [[:foo, :bar], [1, 2]].to_h
|
|
# # => {:foo => :bar, 1 => 2}
|
|
# [1, 2].to_h{|x| [x, x*2]}
|
|
# # => {1 => 2, 2 => 4}
|
|
#
|
|
def to_h(&blk)
|
|
h = {}
|
|
self.each do |v|
|
|
v = blk.call(v) if blk
|
|
raise TypeError, "wrong element type #{v.class}" unless Array === v
|
|
raise ArgumentError, "wrong array length (expected 2, was #{v.length})" unless v.length == 2
|
|
h[v[0]] = v[1]
|
|
end
|
|
h
|
|
end
|
|
|
|
alias append push
|
|
alias prepend unshift
|
|
alias filter! select!
|
|
|
|
##
|
|
# call-seq:
|
|
# ary.fetch_values(idx, ...) -> array
|
|
# ary.fetch_values(idx, ...) { |i| block } -> array
|
|
#
|
|
# Returns an array containing the values associated with the given indexes.
|
|
# but also raises `IndexError` when one of indexes can't be found.
|
|
# Also see `Array#values_at` and `Array#fetch`.
|
|
#
|
|
# a = ["cat", "dog", "cow"]
|
|
#
|
|
# a.fetch_values(2, 0) #=> ["cow", "cat"]
|
|
# a.fetch_values(2, 5) # raises KeyError
|
|
# a.fetch_values(2, 5) {|i| "BIRD" } #=> ["cow", "BIRD"]
|
|
#
|
|
def fetch_values(*idx, &block)
|
|
if block
|
|
idx.map do |i|
|
|
self.fetch(i, &block)
|
|
end
|
|
else
|
|
# Fast path: use C implementation for non-block cases
|
|
idx.map do |i|
|
|
__fetch(i, NONE, NONE)
|
|
end
|
|
end
|
|
end
|
|
|
|
##
|
|
# call-seq:
|
|
# ary.product(*arys) -> array
|
|
# ary.product(*arys) { |item| ... } -> self
|
|
def product(*arys, &block)
|
|
gen = __product_generate(arys, &block)
|
|
return gen unless block
|
|
|
|
if gen
|
|
while group = __product_next(arys, gen)
|
|
yield group
|
|
end
|
|
end
|
|
self
|
|
end
|
|
|
|
##
|
|
# call-seq:
|
|
# ary.repeated_combination(n) { |combination| ... } -> ary
|
|
# ary.repeated_combination(n) -> Enumerator
|
|
#
|
|
# When invoked with a block, yields all length `n` combinations of elements
|
|
# from the array, with replacement, and then returns the array itself.
|
|
#
|
|
# This means that, unlike `combination`, elements can be chosen more than once.
|
|
#
|
|
# The implementation makes no guarantees about the order in which the
|
|
# combinations are yielded.
|
|
#
|
|
# If no block is given, an Enumerator is returned instead.
|
|
#
|
|
# Examples:
|
|
#
|
|
# a = [1, 2, 3]
|
|
# a.repeated_combination(2).to_a #=> [[1,1],[1,2],[1,3],[2,2],[2,3],[3,3]]
|
|
def repeated_combination(n, &block)
|
|
raise TypeError, "no implicit conversion into Integer" unless 0 <=> n
|
|
return to_enum(:repeated_combination, n) unless block
|
|
__repeated_combination(n, false, &block)
|
|
end
|
|
|
|
##
|
|
# call-seq:
|
|
# ary.repeated_permutation(n) { |permutation| ... } -> ary
|
|
# ary.repeated_permutation(n) -> Enumerator
|
|
#
|
|
# When invoked with a block, yields all length `n` permutations of elements
|
|
# from the array, with replacement, and then returns the array itself.
|
|
#
|
|
# This means that, unlike `permutation`, elements can be chosen more than once.
|
|
#
|
|
# The implementation makes no guarantees about the order in which the
|
|
# permutations are yielded.
|
|
#
|
|
# If no block is given, an Enumerator is returned instead.
|
|
#
|
|
# Examples:
|
|
#
|
|
# a = [1, 2]
|
|
# a.repeated_permutation(2).to_a #=> [[1,1],[1,2],[2,1],[2,2]]
|
|
def repeated_permutation(n, &block)
|
|
n = n.__to_int
|
|
raise TypeError, "no implicit conversion into Integer" unless 0 <=> n
|
|
return to_enum(:repeated_permutation, n) unless block
|
|
__repeated_combination(n, true, &block)
|
|
end
|
|
|
|
def __repeated_combination(n, permutation, &block)
|
|
n = n.__to_int
|
|
case n
|
|
when 0
|
|
yield []
|
|
when 1
|
|
# Keep fast Ruby path for n=1
|
|
i = 0
|
|
while i < self.size
|
|
yield [self[i]]
|
|
i += 1
|
|
end
|
|
else
|
|
if n > 0
|
|
# Use C iterator for complex cases
|
|
state = __combination_init(n, permutation)
|
|
while (indices = __combination_next(state))
|
|
# Convert indices to elements in Ruby
|
|
tmp = [nil] * n
|
|
i = 0
|
|
while i < n
|
|
tmp[i] = self[indices[i]]
|
|
i += 1
|
|
end
|
|
yield tmp
|
|
end
|
|
end
|
|
end
|
|
|
|
self
|
|
end
|
|
|
|
##
|
|
# call-seq:
|
|
# ary.find(ifnone = nil) { |elem| block } -> obj or nil
|
|
# ary.find(ifnone = nil) -> Enumerator
|
|
#
|
|
# Returns the first element for which the block returns a true value.
|
|
# If no element matches and +ifnone+ is given, calls +ifnone+ and
|
|
# returns its result. Otherwise returns +nil+.
|
|
#
|
|
# This is an optimized version of Enumerable#find for arrays.
|
|
#
|
|
# [1, 2, 3, 4].find { |x| x > 2 } #=> 3
|
|
# [1, 2, 3, 4].find { |x| x > 10 } #=> nil
|
|
# [1, 2, 3, 4].find(->{0}) { |x| x > 10 } #=> 0
|
|
#
|
|
def find(ifnone=nil, &block)
|
|
return to_enum(:find, ifnone) unless block
|
|
|
|
idx = 0
|
|
len = self.size
|
|
while idx < len
|
|
elem = self[idx]
|
|
return elem if block.call(elem)
|
|
idx += 1
|
|
end
|
|
ifnone&.call
|
|
end
|
|
|
|
##
|
|
# call-seq:
|
|
# ary.rfind(ifnone = nil) { |elem| block } -> obj or nil
|
|
# ary.rfind(ifnone = nil) -> Enumerator
|
|
#
|
|
# Returns the last element for which the block returns a true value.
|
|
# Searches from the end of the array to the beginning.
|
|
# If no element matches and +ifnone+ is given, calls +ifnone+ and
|
|
# returns its result. Otherwise returns +nil+.
|
|
#
|
|
# [1, 2, 3, 4, 3].rfind { |x| x == 3 } #=> 3 (the last one)
|
|
# [1, 2, 3, 4].rfind { |x| x > 2 } #=> 4
|
|
# [1, 2, 3, 4].rfind { |x| x > 10 } #=> nil
|
|
# [1, 2, 3, 4].rfind(->{0}) { |x| x > 10 } #=> 0
|
|
#
|
|
def rfind(ifnone=nil, &block)
|
|
return to_enum(:rfind, ifnone) unless block
|
|
|
|
idx = self.size - 1
|
|
while idx >= 0
|
|
elem = self[idx]
|
|
return elem if block.call(elem)
|
|
idx -= 1
|
|
end
|
|
ifnone&.call
|
|
end
|
|
end
|