syntax_data: {"ast_node_type":"other","tokens":[{"end":100,"kind":"keyword","start":0,"text":"if"}]}
source_snippet:                         if else_block.is_some() { LetSource::LetElse } else { LetSource::PlainLet };
context_before:                     let let_source =
context_after:                     this.with_let_source(let_source, |this| {