Error Boundary - Keyword based

packages/@ember/-internals/glimmer/lib/components/error-boundary.ts

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+import { setComponentTemplate } from '@glimmer/manager/lib/public/template';
+import { templateOnlyComponent } from '@glimmer/runtime/lib/component/template-only';
+
+import ErrorBoundaryTemplate from '../templates/error-boundary';
+
+/**
+ * A template-only `<ErrorBoundary>` whose layout is a single `{{#try}}`. Its
+ * `<:try>` and `<:catch>` are named blocks, so unlike the keyword's clauses
+ * they can be written in either order.
+ */
+const ErrorBoundary = setComponentTemplate(
+  ErrorBoundaryTemplate,
+  templateOnlyComponent(
+    'packages/@ember/-internals/glimmer/lib/components/error-boundary',
+    'ErrorBoundary'
+  )
+);
+
+export default ErrorBoundary;

packages/@ember/-internals/glimmer/lib/templates/error-boundary.ts

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+import { precompileTemplate } from '@ember/template-compilation';
+
+/**
+ * The whole of `<ErrorBoundary>`: a `{{#try}}` that yields to the `<:try>` and
+ * `<:catch>` blocks. A boundary with no fallback uses `{{#try}}` directly, so
+ * there is no default-block form.
+ */
+export default precompileTemplate(
+  `{{#try}}{{yield to="try"}}{{catch as |error retry|}}{{yield error retry to="catch"}}{{/try}}`,
+  {
+    moduleName: 'packages/@ember/-internals/glimmer/lib/templates/error-boundary.hbs',
+    strictMode: true,
+    scope() {
+      return {};
+    },
+  }
+);