protected void validateAlias(String from, String to) {
		if (from.equals("")) {
			throw new IllegalArgumentException("Key '' cannot be an alias");
		}
		if (to.equals("")) {
			throw new IllegalArgumentException("Cannot alias to key '' (from %s)".formatted(from));
		}
	}
Define the schema for a child attribute.

<p>
If the attribute schema's name is empty, the given schema becomes the default attribute
schema.

@param schema the attribute schema to add to the definition
@param origin optional, for diagnostics, an object describing the attribute schema's origin
@return this builder
Ghidra/Debug/Framework-TraceModeling/src/main/java/ghidra/trace/model/target/schema/SchemaBuilder.java