syntax_data: {"ast_node_type":"variable","tokens":[{"end":51,"kind":"keyword","start":0,"text":"let"}]}
source_snippet:     let mut a = &a.chars().collect::<Vec<_>>()[..];
context_before: pub fn edit_distance(a: &str, b: &str, limit: usize) -> Option<usize> {
context_after:     let mut b = &b.chars().collect::<Vec<_>>()[..];