forked from sathish316/metaprogramming_koans
/
about_binding.rb
62 lines (49 loc) · 1.27 KB
/
about_binding.rb
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require File.expand_path(File.dirname(__FILE__) + '/edgecase')
class AboutBinding < EdgeCase::Koan
class Foo
def initialize
@ivar = 22
end
def bar(param)
lvar = 11
binding
end
end
def test_binding_binds_method_parameters
binding = Foo.new.bar(99)
assert_equal __, eval("param", binding)
end
def test_binding_binds_local_vars
binding = Foo.new.bar(99)
assert_equal __, eval("lvar", binding)
end
def test_binding_binds_instance_vars
binding = Foo.new.bar(99)
assert_equal __, eval("@ivar", binding)
end
def test_binding_binds_blocks
binding = Foo.new.bar(99) { 33 }
assert_equal __, eval("yield", binding)
end
def test_binding_binds_self
foo = Foo.new
binding = foo.bar(99)
assert_equal __, eval("self", binding)
end
def n_times(n)
lambda {|value| n * value}
end
def test_lambda_binds_to_the_surrounding_context
two_times = n_times(2)
assert_equal __, two_times.call(3)
end
def count_with_increment(start, inc)
lambda { start += inc}
end
def test_lambda_remembers_state_of_bound_variables
counter = count_with_increment(7, 3)
assert_equal __, counter.call
assert_equal __, counter.call
assert_equal __, counter.call
end
end