Add ability to get iso array from an iso string.

[dipinhora]

No description provided.

[jemc]

I think this qualifies for "principle of least surprise" for bypassing the RFC process.

Any others think differently before I merge?

[EpicEric]

I am not a fan of the method with iso in its name. Perhaps something like data or something better?

[jemc]

@EpicEric - I tend to agree that using iso in a method name is not ideal, but note that this PR is just following the precedent set by the from_array/from_iso_array methods.

ponyc/packages/builtin/string.pony

Lines 61 to 78 in a832cf1

	new val from_array(data: Array[U8] val) =>
	"""
	Create a string from an array, reusing the underlying data pointer.
	"""
	_size = data.size()
	_alloc = data.space()
	_ptr = data.cpointer()._unsafe()
	new iso from_iso_array(data: Array[U8] iso) =>
	"""
	Create a string from an array, reusing the underlying data pointer
	"""
	_size = data.size()
	_alloc = data.space()
	_ptr = (consume data).cpointer()._unsafe()
	if _alloc > _size then
	_set(_size, 0)
	end

[SeanTAllen]

@dipinhora can you add release notes for this?

[dipinhora]

@SeanTAllen is the commit message not adequate for what the release notes require?

[SeanTAllen]

@dipinhora I'm not seeing a commit message.

[dipinhora]

@SeanTAllen The commit message was the one line title only (Add ability to get iso array from an iso string.) but I suppose that's not going to be sufficient for the release notes.

How's the following?

It is now possible to consume a string iso to get the underlying Array[U8] iso for when it is important to convert a string to an array but retain the ability to modify it afterwards.