fn pub static new(keywords: ref Array[String]) -> Keywords {
  let words = Set.new
  let first = ByteArray.filled(with: 0, times: 255)
  let second = ByteArray.filled(with: 0, times: 255)

  for word in keywords.iter.select(fn (w) { w.size >= 2 }) {
    let bytes = word.to_byte_array

    first.set(bytes.get(0).or_panic, 1)
    second.set(bytes.get(1).or_panic, 1)
    words.insert(bytes)
  }

  Keywords(words: words, first: first, second: second)
}

fn pub static new(keywords: ref Array[String]) -> Keywords

Returns a new Keywords populated using the list of keywords.

Examples

import syntax (Keywords)

Keywords.new(['fn', 'class', 'async'])

fn pub contains_range?(bytes: ref ByteArray, at: Int, end: Int) -> Bool {
  (end - at) >= 2
    and @first.get(bytes.get(at).or_panic).or_panic == 1
    and @second.get(bytes.get(at + 1).or_panic).or_panic == 1
    and @words.contains?(bytes.slice(at, end).to_byte_array)
}

fn pub contains_range?(bytes: ref ByteArray, at: Int, end: Int) -> Bool

Returns true if the range of bytes in bytes is a valid keyword.

In the best case scenario, this method doesn't perform any allocations (e.g. the first two bytes don't match any known keywords). In the worst case it slices bytes into a subslice and compares that to the known list of keywords.

The bytes argument is a ByteArray (e.g. a reusable buffer) to check.

The at and end arguments specify the start and end indexes to bytes respectively.

Panics

This method panics if the range is not within bounds.

Examples

import syntax (Keywords)

let kw = Keywords.new(['class', 'async', 'fn'])
let input = 'class'.to_byte_array

kw.contains_range?(input, at: 0, end: 5) # => true