Module: Kernel

Defined in:
lib/shenanigans/kernel/fn.rb,
lib/shenanigans/kernel/with.rb,
lib/shenanigans/kernel/prompt.rb

Constant Summary collapse

CONVERSIONS =

Currently only used by prompt: :to_i, :to_f, :to_r, :to_sym, :to_c

[:to_i, :to_f, :to_r, :to_sym, :to_c]

Instance Method Summary collapse

Instance Method Details

#fn(*funs) ⇒ Object

Composes a list of functions. Functions can be specified as symbols or lambdas.

["foo bar", "baz qux"].map &fn(:split, :last)
#=> ["bar", "qux"]

(1..3).map &fn(:next, -> x { x * x }, -> x { x.to_f / 2 } )
#=> [2.0, 4.5, 8.0]



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# File 'lib/shenanigans/kernel/fn.rb', line 9

def fn(*funs)
  -> x do
    funs.inject(x) do |v,f|
      Proc === f ? f.call(v) : v.send(f)
    end
  end
end

#prompt(text = '', conversion = nil) ⇒ Object

Displays a prompt and returns chomped input. Modelled after the Python method raw_input, but also can be supplied with an optional conversion method.

prompt("Prompt> ")
Prompt> 12
#=> "12"

prompt("Prompt> ", :to_f)
Prompt> 12
#=> 12.0



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# File 'lib/shenanigans/kernel/prompt.rb', line 17

def prompt(text='', conversion=nil)
  print text unless text.empty?
  input = gets.chomp
  CONVERSIONS.include?(conversion) ? input.send(conversion) : input
end

#with(o, &blk) ⇒ Object

A Pascal/ActionScript like with method. Yields its argument to the provided block and then returns it.

with([]) do |a|
  a << "a"
  a << "b"
end
#=> ["a", "b"]



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# File 'lib/shenanigans/kernel/with.rb', line 9

def with(o, &blk)
  o.tap(&blk)
end