Elixir v1.8.0 StringIO View Source
Controls an IO device process that wraps a string.
A StringIO IO device can be passed as a "device" to
most of the functions in the IO module.
Examples
iex> {:ok, pid} = StringIO.open("foo")
iex> IO.read(pid, 2)
"fo"Link to this section Summary
Functions
Returns a specification to start this module under a supervisor.
Stops the IO device and returns the remaining input/output buffers.
Returns the current input/output buffers for the given IO device.
Flushes the output buffer and returns its current contents.
Creates an IO device.
Creates an IO device.
Link to this section Functions
Returns a specification to start this module under a supervisor.
See Supervisor.
Specs
Stops the IO device and returns the remaining input/output buffers.
Examples
iex> {:ok, pid} = StringIO.open("in")
iex> IO.write(pid, "out")
iex> StringIO.close(pid)
{:ok, {"in", "out"}}Specs
Returns the current input/output buffers for the given IO device.
Examples
iex> {:ok, pid} = StringIO.open("in")
iex> IO.write(pid, "out")
iex> StringIO.contents(pid)
{"in", "out"}Specs
Flushes the output buffer and returns its current contents.
Examples
iex> {:ok, pid} = StringIO.open("in")
iex> IO.write(pid, "out")
iex> StringIO.flush(pid)
"out"
iex> StringIO.contents(pid)
{"in", ""}Specs
open(binary(), keyword()) :: {:ok, pid()}
open(binary(), (pid() -> res)) :: {:ok, res} when res: var
Creates an IO device.
string will be the initial input of the newly created
device.
options_or_function can be a keyword list of options or
a function.
If options are provided, the result will be {:ok, pid}, returning the
IO device created. The option :capture_prompt, when set to true, causes
prompts (which are specified as arguments to IO.get* functions) to be
included in the device's output.
If a function is provided, the device will be created and sent to the
function. When the function returns, the device will be closed. The final
result will be a tuple with :ok and the result of the function.
Examples
iex> {:ok, pid} = StringIO.open("foo")
iex> IO.gets(pid, ">")
"foo"
iex> StringIO.contents(pid)
{"", ""}
iex> {:ok, pid} = StringIO.open("foo", capture_prompt: true)
iex> IO.gets(pid, ">")
"foo"
iex> StringIO.contents(pid)
{"", ">"}
iex> StringIO.open("foo", fn pid ->
...> input = IO.gets(pid, ">")
...> IO.write(pid, "The input was #{input}")
...> StringIO.contents(pid)
...> end)
{:ok, {"", "The input was foo"}}Specs
Creates an IO device.
string will be the initial input of the newly created
device.
If the :capture_prompt option is set to true,
prompts (specified as arguments to IO.get* functions)
are captured in the output.
The device will be created and sent to the function given.
When the function returns, the device will be closed. The final
result will be a tuple with :ok and the result of the function.
Examples
iex> StringIO.open("foo", [], fn pid ->
...> input = IO.gets(pid, ">")
...> IO.write(pid, "The input was #{input}")
...> StringIO.contents(pid)
...> end)
{:ok, {"", "The input was foo"}}
iex> StringIO.open("foo", [capture_prompt: true], fn pid ->
...> input = IO.gets(pid, ">")
...> IO.write(pid, "The input was #{input}")
...> StringIO.contents(pid)
...> end)
{:ok, {"", ">The input was foo"}}