Add space around vertical bar (#733)

Author: eksperimental

_posts/2012-04-24-a-peek-inside-elixir-s-parallel-compiler.markdown

@@ -14,7 +14,7 @@ The idea of the parallel compiler is very simple: for each file we want to compi
 
 In Elixir, we could write this code as follows:
 
-    def spawn_compilers([current|files], output) do
+    def spawn_compilers([current | files], output) do
       parent = Process.self()
       child  = spawn_link(fn ->
         :elixir_compiler.file_to_path(current, output)
@@ -32,7 +32,7 @@ In Elixir, we could write this code as follows:
       :done
     end
 
-In the first line, we define a function named `spawn_compilers` that receives two arguments, the first is a list of files to compile and the second is a string telling us where to write the compiled file. The first argument is represented as a list with head and tail (`[current|files]`) where the top of the list is assigned to `current` and the remaining items to `files`. If the list is empty, the first clause of `spawn_compilers` is not going to match, the clause `spawn_compilers([], _output)` defined at the end will instead.
+In the first line, we define a function named `spawn_compilers` that receives two arguments, the first is a list of files to compile and the second is a string telling us where to write the compiled file. The first argument is represented as a list with head and tail (`[current | files]`) where the top of the list is assigned to `current` and the remaining items to `files`. If the list is empty, the first clause of `spawn_compilers` is not going to match, the clause `spawn_compilers([], _output)` defined at the end will instead.
 
 Inside `spawn_compilers`, we first retrieve the PID of the current process with `Process.self` (remember we are talking about Erlang processes/actors and not OS processes) and then proceed to spawn a new process to execute the given function in parallel. Spawning a new process is done with the `spawn_link` function.
 
@@ -121,13 +121,13 @@ Notice that we have two small additions. First we store the `:elixir_parent_comp
 
 Second, our main process can now receive a new `{ :waiting, child, module }` message, so we need to extend it to account for those messages. Not only that, we need to control which PIDs we have spawned so we can notify them whenever a new module is compiled, forcing us to add a new argument to the `spawn_compilers` function. `spawn_compilers` would then be rewritten as follows:
 
-    def spawn_compilers([current|files], output, stack) do
+    def spawn_compilers([current | files], output, stack) do
       parent = Process.self()
       child  = spawn_link(fn ->
         :elixir_compiler.file_to_path(current, output)
         send parent, { :compiled, Process.self() }
       end)
-      wait_for_messages(files, output, [child|stack])
+      wait_for_messages(files, output, [child | stack])
     end
 
     # No more files and stack is empty, we are done

_posts/2013-05-23-elixir-v0-9-0-released.markdown

@@ -77,7 +77,7 @@ defimpl Enumerable, for: List do
     do_reduce(list, acc, fun)
   end
 
-  defp do_reduce([h|t], acc, fun) do
+  defp do_reduce([h | t], acc, fun) do
     do_reduce(t, fun.(h, acc), fun)
   end
 
@@ -101,7 +101,7 @@ The `Enum.map/2` we have used above is now implemented in terms of this reducing
 defmodule Enum do
   def map(collection, fun) do
     Enumerable.reduce(collection, [], fn(x, acc) ->
-      [fun.(x, acc)|acc]
+      [fun.(x, acc) | acc]
     end) |> reverse
   end
 end

_posts/2013-12-11-elixir-s-new-continuable-enumerators.markdown

@@ -152,7 +152,7 @@ function.
 ```elixir
 defmodule Interleave do
   def interleave(a, b) do
-    step = fn x, acc -> { :suspend, [x|acc] } end
+    step = fn x, acc -> { :suspend, [x | acc] } end
     af = &Enumerable.reduce(a, &1, step)
     bf = &Enumerable.reduce(b, &1, step)
     do_interleave(af, bf, []) |> :lists.reverse()

crash-course.markdown

@@ -461,7 +461,7 @@ Pattern matching in Elixir is based on Erlang's implementation and in general is
 **Erlang**
 
 ```erlang
-loop_through([H|T]) ->
+loop_through([H | T]) ->
   io:format('~p~n', [H]),
   loop_through(T);
 
@@ -472,7 +472,7 @@ loop_through([]) ->
 **Elixir**
 
 ```elixir
-def loop_through([h|t]) do
+def loop_through([h | t]) do
   IO.inspect h
   loop_through t
 end

getting-started/basic-types.markdown

@@ -348,7 +348,7 @@ What is the difference between lists and tuples?
 Lists are stored in memory as linked lists, meaning that each element in a list holds its value and points to the following element until the end of the list is reached. We call each pair of value and pointer a **cons cell**:
 
 ```iex
-iex> list = [1|[2|[3|[]]]]
+iex> list = [1 | [2 | [3 | []]]]
 [1, 2, 3]
 ```
 

getting-started/meta/domain-specific-languages.markdown

@@ -165,7 +165,7 @@ defmodule TestCase do
     function_name = String.to_atom("test " <> description)
     quote do
       # Prepend the newly defined test to the list of tests
-      @tests [unquote(function_name)|@tests]
+      @tests [unquote(function_name) | @tests]
       def unquote(function_name)(), do: unquote(block)
     end
   end

getting-started/mix-otp/agent.markdown

@@ -40,7 +40,7 @@ And play a bit with agents:
 ```iex
 iex> {:ok, agent} = Agent.start_link fn -> [] end
 {:ok, #PID<0.57.0>}
-iex> Agent.update(agent, fn list -> ["eggs"|list] end)
+iex> Agent.update(agent, fn list -> ["eggs" | list] end)
 :ok
 iex> Agent.get(agent, fn list -> list end)
 ["eggs"]

getting-started/pattern-matching.markdown

@@ -102,7 +102,7 @@ iex> tail
 Similar to the `hd/1` and `tl/1` functions, we can't match an empty list with a head and tail pattern:
 
 ```iex
-iex> [h|t] = []
+iex> [h | t] = []
 ** (MatchError) no match of right hand side value: []
 ```
 
@@ -111,7 +111,7 @@ The `[head | tail]` format is not only used on pattern matching but also for pre
 ```iex
 iex> list = [1, 2, 3]
 [1, 2, 3]
-iex> [0|list]
+iex> [0 | list]
 [0, 1, 2, 3]
 ```
 
@@ -162,7 +162,7 @@ iex> {x, x} = {1, 2}
 In some cases, you don't care about a particular value in a pattern. It is a common practice to bind those values to the underscore, `_`. For example, if only the head of the list matters to us, we can assign the tail to underscore:
 
 ```iex
-iex> [h|_] = [1, 2, 3]
+iex> [h | _] = [1, 2, 3]
 [1, 2, 3]
 iex> h
 1

getting-started/recursion.markdown

@@ -56,7 +56,7 @@ Let's now see how we can use the power of recursion to sum a list of numbers:
 
 ```elixir
 defmodule Math do
-  def sum_list([head|tail], accumulator) do
+  def sum_list([head | tail], accumulator) do
     sum_list(tail, head + accumulator)
   end
 
@@ -68,9 +68,9 @@ end
 IO.puts Math.sum_list([1, 2, 3], 0) #=> 6
 ```
 
-We invoke `sum_list` with the list `[1, 2, 3]` and the initial value `0` as arguments. We will try each clause until we find one that matches according to the pattern matching rules. In this case, the list `[1, 2, 3]` matches against `[head|tail]` which binds `head` to `1` and `tail` to `[2, 3]`; `accumulator` is set to `0`.
+We invoke `sum_list` with the list `[1, 2, 3]` and the initial value `0` as arguments. We will try each clause until we find one that matches according to the pattern matching rules. In this case, the list `[1, 2, 3]` matches against `[head | tail]` which binds `head` to `1` and `tail` to `[2, 3]`; `accumulator` is set to `0`.
 
-Then, we add the head of the list to the accumulator `head + accumulator` and call `sum_list` again, recursively, passing the tail of the list as its first argument. The tail will once again match `[head|tail]` until the list is empty, as seen below:
+Then, we add the head of the list to the accumulator `head + accumulator` and call `sum_list` again, recursively, passing the tail of the list as its first argument. The tail will once again match `[head | tail]` until the list is empty, as seen below:
 
 ```elixir
 sum_list [1, 2, 3], 0
@@ -87,8 +87,8 @@ What if we instead want to double all of the values in our list?
 
 ```elixir
 defmodule Math do
-  def double_each([head|tail]) do
-    [head * 2|double_each(tail)]
+  def double_each([head | tail]) do
+    [head * 2 | double_each(tail)]
   end
 
   def double_each([]) do