Components, templates, and slots

PXML components are compile-time macros with typed properties and content slots. They do not add runtime control objects.

Define and use a component

<?pxml version="1.0"?>
<x:Component xmlns:x="urn:pcl:pxml:x" x:Name="ActionCard">
  <x:Property Name="Text" Type="string" Required="true" />
  <x:Property Name="Command" Type="command?" Default="null" />
  <Column Class="action-card" Padding="12" Gap="8">
    <Text Text="{component.Text}" />
    <x:Content />
  </Column>
</x:Component>

<local:ActionCard Text="Compile">
  <Button Text="Start" Command="{cmd Compiler.Build}" />
</local:ActionCard>

Expansion resolves the component, validates properties, fills slots, substitutes component.*, expands nested components, and folds constants.

Named slots use x:Into Slot="Header" / x:Into Slot="Content". Missing required slots, unknown slots, and duplicate fills are diagnostics.

Templates

<x:Template Name="VersionTemplate" Type="VersionModel" As="version">
  <Text Text="{version.Name}" />
</x:Template>
<Content Template="{template VersionTemplate}" Value="{bind SelectedVersion}" />

Template locals are typed, not runtime dictionaries.

Explicit inputs

pxmlc --full Page.pxml -o Page.pxb \
  --component Components/ActionCard.pxml \
  --import Shared/Templates.pxml

x:Import Source resolves only to a file explicitly registered with --import; components use --component. x:Const and x:IfBuild disappear from release blueprints after folding.

Next: Styles, themes, and resources.