Alaja.Wizard (Alaja v2.2.0)

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Declarative multi-field form renderer for Alaja.

A Wizard holds an ordered list of fields (name, label, type, value, default, hint). It does NOT run interactively — it renders to an Alaja.Buffer.t/0 via one of the five neutral renderers:

:inline           — all fields on one line, comma-separated
:compact          — two-column table (label | value)
:stacked          — one field per row, label above value
:wizard           — boxed form with progress marker
:compact_wizard   — boxed form, single-line per field

Renderers are pure: same input, same output Buffer. Use Alaja.Printer.print_raw/2 (or your own Buffer consumer) to flush.

Example

w =
  Alaja.Wizard.new()
  |> Alaja.Wizard.field(:name, :string, label: "Name", default: "alice")
  |> Alaja.Wizard.field(:age, :integer, label: "Age", default: 30)
  |> Alaja.Wizard.field(:newsletter, :boolean, label: "Subscribe?", default: true)

Alaja.Wizard.render(w, :compact) |> Alaja.Printer.print_raw()

See render/2 for the full dispatcher and field/3 for accepted options.

Summary

Types

field()
field_type()
t()

Functions

field(w, name, type, opts \\ [])

Appends a field to the wizard.

new(opts \\ [])

Starts a new empty Wizard.

render(w, renderer \\ nil)

Renders the wizard to an Alaja.Buffer.t/0 using the named renderer.

set(w, name, value)

Sets the value of an existing field by name.

Types

field()

@type field() :: %{
  name: atom(),
  label: String.t(),
  type: field_type(),
  value: any(),
  default: any(),
  hint: String.t() | nil,
  values: [any()] | nil
}

field_type()

@type field_type() :: :string | :integer | :float | :boolean | :enum | :path | :url

t()

@type t() :: %Alaja.Wizard{
  fields: [field()],
  renderer: :inline | :compact | :stacked | :wizard | :compact_wizard,
  title: String.t() | nil
}

Functions

field(w, name, type, opts \\ [])

@spec field(t(), atom(), field_type(), keyword()) :: t()

Appends a field to the wizard.

Options

  • :label — human-readable label (defaults to Atom.to_string(name))
  • :default — default value applied when value is unset
  • :hint — small helper text shown beneath the field
  • :values — for :enum type, the allowed atoms/strings

The current value falls back to :default if :value is not given. Use set/3 to mutate a value in-place on a wizard.

new(opts \\ [])

@spec new(keyword()) :: t()

Starts a new empty Wizard.

Options

  • :title — title rendered at the top of boxed renderers
  • :renderer — default renderer for render/1 (default :compact)

render(w, renderer \\ nil)

@spec render(t(), :inline | :compact | :stacked | :wizard | :compact_wizard | nil) ::
  Alaja.Buffer.t()

Renders the wizard to an Alaja.Buffer.t/0 using the named renderer.

Recognised renderers: :inline, :compact, :stacked, :wizard, :compact_wizard. Any other atom raises ArgumentError.

set(w, name, value)

@spec set(t(), atom(), any()) :: t()

Sets the value of an existing field by name.

Raises ArgumentError if no field with that name exists.