syntax_data: {"ast_node_type":"other","tokens":[{"end":86,"kind":"keyword","start":0,"text":".map(|pos|"}]}
source_snippet:                     .map(|pos| Self::byte(if pos == nz_idx { NONZERO } else { BYTE }))
context_before:                 (0..width_in_bytes)
context_after:                     .fold(Self::unit(), Self::then)