syntax_data: {"ast_node_type":"variable","tokens":[{"end":43,"kind":"keyword","start":0,"text":"if"}]}
source_snippet:             if let Some(expr) = arm.guard {
context_before:         self.with_lint_level(arm.lint_level, |this| {
context_after:                 this.with_let_source(LetSource::IfLetGuard, |this| {