Amokrane

import android.content.Context;
import android.graphics.Canvas;
import android.graphics.LinearGradient;
import android.graphics.Paint;
import android.graphics.Path;
import android.graphics.Shader;
import android.util.AttributeSet;
import android.widget.LinearLayout;

import com.movl.swipeit.R;

Amokrane

def some_method
  @some_method ||= some_expensive_op
end

Amokrane

@list.map(&:to_i)
# vs
@list.map { |x| x.to_i }

Amokrane

def sometimes_block
  if block_given?
    Proc.new.call
  end
end
sometimes_block { puts "hi" }
sometimes_block

Amokrane

class Foo
  def explicit & block
    yield
  end

  def implicit
    yield
  end
end

Amokrane

class Foo
  def foo; end
  define_method :bar do; end
  class_eval %{ def baz; end }
end

Amokrane

lambda {...} # vs 
class Callable
  def call; .. end
end

Amokrane

%w{
  Foo
  Bar
  Baz
}.inject(Object) { |klass, string|
  klass.const_get(string.to_sym)
}

Amokrane

values = some_list.map { |val|
  [val, some_transform(val)]
}
Hash[values]

Amokrane

some_list.inject({}) do |hash, val|
  hash[val] = some_transform(val)
  hash 
end