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// Copyright © 2016 Alan A. A. Donovan & Brian W. Kernighan.
// License: https://creativecommons.org/licenses/by-nc-sa/4.0/

// See page 305.
//!+

// Package word provides utilities for word games.
package word

import "unicode"

// IsPalindrome reports whether s reads the same forward and backward.
// Letter case is ignored, as are non-letters.
func IsPalindrome(s string) bool {
    var letters []rune
    for _, r := range s {
        if unicode.IsLetter(r) {
            letters = append(letters, unicode.ToLower(r))
        }
    }
    for i := range letters {
        if letters[i] != letters[len(letters)-1-i] {
            return false
        }
    }
    return true
}

//!-