Text, {expr}, {@html}

Raw text is the least interesting node and the easiest to get wrong in a printer. It is @prop!"textContent" on the NamedNode that owns it, not a string concatenate on the parent. Concatenate-on-the-parent cannot update. A child NamedNode can.

{ident} is the same idea with a name. The child field is called ident. construct seeds child.ident = ident from the host field (G85). Author this.update.x is rewritten to child.update.x so the live handle moves. That rewrite is why ClickField’s go() does not say this.update.msg on the host and hope; it says msgSpan.update.msg = msg after updating the host field. The printed file is the teacher.

{@html expr} is a wrapper div with @prop!"innerHTML". construct seeds it (rawHtml.raw = raw in Combo.svelte). It is not Eval and it is not a second HTML parser. The browser’s innerHTML is the sink. Treat the expression as you would any other trusted HTML; svelte-d does not grow a sanitizer.

Comments are skipped. {@const x = …} and {let extra = 3} / {const …} become host fields (int / bool / string). They are not reactive. {@debug x} is console.log("x") in onMount, after handles exist, so a debug of a bound value sees the seeded field. {@render snippet()} walks the stored snippet body. {@render pair(who, extra)} assigns each parameter and then walks — multi-param snippets are not a single string bag. {@attach fn} is an onMount call with this.node.handle, which is why it cannot run in construct.

The theme across this page is ownership. Text, mustaches, and HTML all belong to a NamedNode that update can address. A printer that inlined them into the parent’s textContent would be simpler and would be wrong the first time something flipped.