Class: Hash

Inherits:
Object show all
Defined in:
lib/mug/bool.rb,
lib/mug/hashmap.rb

Instance Method Summary collapse

Instance Method Details

#map_keys(&block) ⇒ Object

Returns a new hash which is a copy of the current hash but each key is replaced by the result of running it through block.

If block returns duplicate keys, they will be overwritten in the resulting hash.

{'a'=>1, 'b'=>2}.map_keys { |k| k*2 } #=> {'aa'=>1, 'bb'=>2}
{'a'=>1, 'b'=>2}.map_keys { "cat" }   #=> {'cat'=>2}



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# File 'lib/mug/hashmap.rb', line 37

def map_keys &block # :yields: key
  hsh = {}
  each do |k, v|
    hsh[ yield k ] = v
  end
  hsh
end

#map_keys!(&block) ⇒ Object

Replaces the keys in hsh by running them each through block.

If block returns duplicate keys, they will be overwritten in turn.

See: #map_keys



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# File 'lib/mug/hashmap.rb', line 52

def map_keys! &block # :yields: key
  replace map_keys(&block)
end

#map_pairs(&block) ⇒ Object

Returns a new hash which is a copy of the current hash but each key-value pair is replaced by the result of running it through block.

If block returns duplicate keys, they will be overwritten in the resulting hash.

{'a'=>1, 'b'=>2}.map_pairs { |k,v| [k*2, v+1] } #=> {'aa'=>2, 'bb'=>3}
{'a'=>1, 'b'=>2}.map_pairs { ["cat","dog"] }   #=> {'cat'=>'dog'}



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# File 'lib/mug/hashmap.rb', line 66

def map_pairs &block # :yields: key, value
  hsh = {}
  each do |k, v|
    a, b = yield k, v
    hsh[a] = b
  end
  hsh
end

#map_pairs!(&block) ⇒ Object

Replaces the values in hsh by running them each through block.

See: #map_values



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# File 'lib/mug/hashmap.rb', line 80

def map_pairs! &block # :yields: key, value
  replace map_pairs(&block)
end

#map_values(&block) ⇒ Object

Returns a new hash which is a copy of the current hash but each value is replaced by the result of running it through block.

{'a'=>1, 'b'=>2}.map_values { |v| v*2 } #=> {'a'=>2, 'b'=>4}
{'a'=>1, 'b'=>2}.map_values { "cat" }   #=> {'a'=>"cat", 'b'=>"cat"}



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# File 'lib/mug/hashmap.rb', line 10

def map_values &block # :yields: value
  hsh = {}
  each do |k, v|
    hsh[k] = yield v
  end
  hsh
end

#map_values!(&block) ⇒ Object

Replaces the values in hsh by running them each through block.

See: #map_values



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# File 'lib/mug/hashmap.rb', line 23

def map_values! &block # :yields: value
  replace map_values(&block)
end

#to_b ⇒ Object

Converts hsh to a boolean. Returns true if not empty.



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# File 'lib/mug/bool.rb', line 76

def to_b
  !empty?
end