Riddler.Screens.Resolved (Riddler v0.1.0)

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A document resolved against one visitor's context and responses.

It is the same envelope the document carried - schema_version, kind, id and metadata - with the screens the visitor is actually shown, plus diagnostics. A resolved document with a non-empty diagnostics is still a resolved document: resolution reports what it could not decide, it does not refuse. Refusing is Riddler.Screens.Document.validate/1's job, and it happens before a visitor exists.

kind is the kind the document was decided to belong to, carried through so that a host holding a resolved document can tell what it is holding without the document it came from.

The screens

A resolved screen keeps its key and title and carries its nodes in the order the document declared them, with the nodes a condition hid absent rather than flagged, every container collapsed to its winner, every template field rendered to text, and no condition anywhere: a node that is present is a node that is shown. writes is carried through unchanged, because it is what the host applies when the visitor presses the button.

The diagnostics

missing_variables names each template variable that was absent, together with the key of the node whose template wanted it. undecidable_conditions names each node whose condition could not be evaluated, together with the condition that could not be evaluated. Both are in document order, and both are lists of entries rather than bare keys: one node can want two variables, and a diagnostic that cannot say which variable is a diagnostic an author cannot act on.

Summary

Types

diagnostics()

What resolution reports without refusing.

missing_variable()

A template variable that was absent, and the node that wanted it.

screen()

A resolved screen: the shape of the screen it came from.

t()
undecidable_condition()

A condition that could not be evaluated, and the node carrying it.

Types

diagnostics()

@type diagnostics() :: %{
  missing_variables: [missing_variable()],
  undecidable_conditions: [undecidable_condition()]
}

What resolution reports without refusing.

missing_variable()

@type missing_variable() :: %{key: term(), variable: String.t()}

A template variable that was absent, and the node that wanted it.

screen()

@type screen() :: %{
  key: term(),
  title: term(),
  nodes: [Riddler.Screens.Type.node_t()]
}

A resolved screen: the shape of the screen it came from.

t()

@type t() :: %Riddler.Screens.Resolved{
  diagnostics: diagnostics(),
  id: term(),
  kind: term(),
  metadata: %{optional(String.t()) => term()},
  schema_version: term(),
  screens: [screen()]
}

undecidable_condition()

@type undecidable_condition() :: %{key: term(), condition: term()}

A condition that could not be evaluated, and the node carrying it.