Function cnst

crates/kernel/src/whnf.rs:3527–3529

(name: &str, us: &[AU])

    let is_back = *addr == self.prims.string_back.addr
      || *addr == self.prims.string_legacy_back.addr;
    let is_utf8_byte_size = *addr == self.prims.string_utf8_byte_size.addr;
    let is_to_byte_array = *addr == self.prims.string_to_byte_array.addr;
    if (!is_back && !is_utf8_byte_size && !is_to_byte_array) || args.len() != 1
    {
      return Ok(None);
    }