Emitter 2b: the block-node directives, the pipe table and the refusal corpus

src/directive-attributes.ts

@@ -0,0 +1,35 @@
+import type { JsonValue } from './json-value.ts'
+import { serializeCanonicalJson } from './canonical-json.ts'
+
+export type AttributeKind = 'boolean' | 'json' | 'number' | 'string'
+
+const bareToken = /^[A-Za-z0-9_-]+$/
+
+export function isBareToken(text: string): boolean {
+  return bareToken.test(text)
+}
+
+export function spellAttributes(pairs: readonly (readonly [string, string])[]): string {
+  if (pairs.length === 0) return ''
+  const spelled = [...pairs].sort(([left], [right]) => (left < right ? -1 : 1)).map(([key, value]) => `${key}=${value}`)
+  return `{${spelled.join(' ')}}`
+}
+
+export function spellAttributeValue(value: JsonValue, kind: AttributeKind): string | undefined {
+  if (kind === 'json') return spellJsonAttribute(value)
+  if (kind === 'boolean') return typeof value === 'boolean' ? `${value}` : undefined
+  if (kind === 'number') return typeof value === 'number' ? spell(JSON.stringify(value)) : undefined
+  return typeof value === 'string' ? spell(value) : undefined
+}
+
+export function spellJsonAttribute(value: JsonValue): string {
+  return quote(serializeCanonicalJson(value, 'compact'))
+}
+
+function spell(text: string): string {
+  return isBareToken(text) ? text : quote(text)
+}
+
+function quote(text: string): string {
+  return JSON.stringify(text)
+}