knewter · May 21, 2014 02:46
diff --git a/why.ex b/why.ex
 iex(1)>     increment = &Map.update!(&1, :count, fn(x) -> x + 1 end)
 #Function<6.106461118/1 in :erl_eval.expr/5>
 iex(2)>     increment = fn(x) -> x[:count] = x[:count] + 1 end
 ** (ArgumentError) dynamic access cannot be invoked inside match and guard clauses
    (elixir) expanding macro: Kernel.access/2
    (elixir) iex:2: :elixir_compiler.__FILE__/2
 iex(2)>
	iex(1)> increment = &Map.update!(&1, :count, fn(x) -> x + 1 end)
	#Function<6.106461118/1 in :erl_eval.expr/5>
	iex(2)> increment = fn(x) -> x[:count] = x[:count] + 1 end
	** (ArgumentError) dynamic access cannot be invoked inside match and guard clauses
	(elixir) expanding macro: Kernel.access/2
	(elixir) iex:2: :elixir_compiler.__FILE__/2
	iex(2)>