syntax_data: {"ast_node_type":"variable","tokens":[{"end":72,"kind":"keyword","start":0,"text":"//"}]}
source_snippet:                     // enclosing the rest of the `let .. else ..` parts.
context_before:                     // Lower the `else` block first because its parent scope is actually
context_after:                     let else_block_span = this.thir[*else_block].span;