plymio_ast_vorm v0.1.0 Plymio.Ast.Vorm.Field View Source
Convenience wrappers for using a vorm held in a struct.
Most of these wrappers assumes a vorm is, or will be, held in the :vorm field of a struct and allow function such as add to be called where the first argument is the struct. For example struct_vorm_add looks like:
def struct_vorm_add(struct, new_forms) do
with {:ok, %{vorm: %Plymio.Ast.Vorm{} = vorm} = struct <- struct |> struct_vorm_ensure,
{:ok, %Plymio.Ast.Vorm{} = vorm} <- vorm |> Plymio.Ast.Vorm.add(new_forms) do
{:ok, struct |> struct!(vorm: vorm)
else
{:error, _} = result -> result
end
endSince most of the wrappers work in the same way, only
struct_vorm_addwill be documented below with illustrative examples.
Documentation Terms
In the documentation below these terms, usually in italics, are used to mean the same thing (e.g. state).
vorm
An instance of Plymio.Ast.Vorm (%Plymio.Ast.Vorm{}).
vorm field
The field called :vorm in a struct intended to hold a vorm.
state
A instance of a struct with a vorm field.
Link to this section Summary
Functions
struct_forms_update/2 take a state and a second argument
struct_vorm_add/2 appends new_forms to the vorm forms of the vorm in the vorm field
struct_vorm_ensure/1 take a state and checks if the vorm field already holds a vorm
struct_vorm_reset/1 take a state and resets its vorm field to nil returning {:ok, state}
struct_vorm_update/2 take a state and a second argument
Link to this section Types
Link to this section Functions
struct_forms_update/2 take a state and a second argument.
If the second argument is a vorm, the state is updated with the vorm’s forms and {:ok, state} returned.
Otherwise the second argument is assumed to be one or more forms and the state is updated with them, returning {:ok, state}.
Examples
iex> {:ok, vorm} = Plymio.Ast.Vorm.new(form: quote(do: x = x + 1))
...> t = %PlymioAstVormFieldTest{}
...> {:ok, t} = t |> struct_forms_update(vorm)
...> t.vorm |> helper_vorm_test_forms!(binding: [x: 3])
{4, ["x = x + 1"]}
iex> t = %PlymioAstVormFieldTest{}
...> {:ok, t} = t |> struct_forms_update(forms: quote(do: x = x + 1))
...> t.vorm |> helper_vorm_test_forms!(binding: [x: 3])
{4, ["x = x + 1"]}
iex> t = %PlymioAstVormFieldTest{}
...> {:ok, t} = t |> struct_forms_update(:a_valid_ast)
...> t.vorm |> helper_vorm_test_forms!(binding: [x: 3])
{:a_valid_ast, [":a_valid_ast"]}struct_vorm_add/2 appends new_forms to the vorm forms of the vorm in the vorm field.
struct_vorm_ensure/1 is called first to ensure the vorm field is a vorm.
If the add suceeds, {:ok, state} is returned.
Examples
iex> t = %PlymioAstVormFieldTest{}
...> {:ok, t} = t |> struct_vorm_add(quote(do: x = x + 1))
...> t.vorm |> helper_vorm_test_forms!(binding: [x: 7])
{8, ["x = x + 1"]}
iex> t = %PlymioAstVormFieldTest{}
...> {:ok, t} = t |> struct_vorm_add(quote(do: x = x + 1))
...> {:ok, t} = t |> struct_vorm_add([quote(do: x = x * x), quote(do: x = x - 1)])
...> t.vorm |> helper_vorm_test_forms!(binding: [x: 7])
{63, ["x = x + 1", "x = x * x", "x = x - 1"]}struct_vorm_ensure/1 take a state and checks if the vorm field already holds a vorm.
If it has {:ok, state} is returned.
If the vorm field is nil, a new, empty vorm is created, stored in the vorm field, and {:ok, state} returned.
Any other value in the vorm field will cause an error.
Examples
iex> t = %PlymioAstVormFieldTest{}
...> match?(nil, t.vorm)
true
iex> {:ok, t} = %PlymioAstVormFieldTest{}
...> |> struct_vorm_ensure
...> match?(%Plymio.Ast.Vorm{}, t.vorm)
true
iex> {:ok, vorm} = Plymio.Ast.Vorm.new(form: quote(do: x = x + 1))
...> {:ok, t} = %PlymioAstVormFieldTest{vorm: vorm}
...> |> struct_vorm_ensure
...> t.vorm |> helper_vorm_test_forms!(binding: [x: 3])
{4, ["x = x + 1"]}
iex> %PlymioAstVormFieldTest{vorm: :not_a_vorm}
...> |> struct_vorm_ensure
{:error, %Plymio.Ast.Vorm.Error{error: nil, message: "vorm field invalid",
value: %PlymioAstVormFieldTest{vorm: :not_a_vorm}}}struct_vorm_reset/1 take a state and resets its vorm field to nil returning {:ok, state}.
Examples
iex> t = %PlymioAstVormFieldTest{}
...> {:ok, t} = t |> struct_vorm_reset
...> match?(nil, t.vorm)
true
iex> {:ok, vorm} = Plymio.Ast.Vorm.new(form: quote(do: x = x + 1))
...> {:ok, t} = %PlymioAstVormFieldTest{vorm: vorm}
...> |> struct_vorm_reset
...> match?(nil, t.vorm)
truestruct_vorm_update/2 take a state and a second argument.
If the second argument is a vorm, the state is updated with it and {:ok, state} returned.
Otherwise the second argument is passed to new/1 and the new vorm stored in the state.
Examples
iex> {:ok, vorm} = Plymio.Ast.Vorm.new(form: quote(do: x = x + 1))
...> t = %PlymioAstVormFieldTest{}
...> {:ok, t} = t |> struct_vorm_update(vorm)
...> t.vorm |> helper_vorm_test_forms!(binding: [x: 3])
{4, ["x = x + 1"]}
iex> t = %PlymioAstVormFieldTest{}
...> {:ok, t} = t |> struct_vorm_update(forms: quote(do: x = x + 1))
...> t.vorm |> helper_vorm_test_forms!(binding: [x: 3])
{4, ["x = x + 1"]}
iex> t = %PlymioAstVormFieldTest{}
...> t |> struct_vorm_update(:not_new_opts)
{:error, %Plymio.Ast.Vorm.Error{error: nil, message: "new vorm opts invalid", value: :not_new_opts}}