ch7ex10

README

= Exercise 7.10
// Refs:
:chapter: 7
:exercise: 10
:url-base: https://github.com/fenegroni/TGPL-exercise-solutions
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{badge-exercise}

The `sort.Interface` type can be adapted to other uses.
Write a function
`IsPalindrome(s sort.Interface) bool`
that
reports whether the sequence `s` is a palindrome,
in other words,
reversing the sequence would not change it.
Assume that the elements at indices `i` and `j` are equal
if `!s.Less(i, j) && !s.Less(j, i)`.

== Test

The implementation of `IsPalindrome` using `sort.Interface` is straightforward.

We test with two different types: `string` and `[]rune`.

=== Using `String`

Type `String` gives the builtin `string` type the `sort.Interface` methods we need.

It shows that to add an interface to a built in type like string we need to create an alias.

=== Using `RuneSlice`

`RuneSlice`, defined as an alias for `[]rune`, gives us the opportunity
to validate more than just prefectly symmetrical byte strings.

=== Using `CaseInsensitiveString`

The basic tests for `RuneSlice` don't look particularly promising,
but the adapter type `CaseInsensitiveString` shows the greater flexibility of converting
a utf8 `string` into a `RuneSlice` and adapting it to a case insensitive unicode string.

Documentation

Index

• func IsPalindrome(s sort.Interface) bool

Functions

func IsPalindrome

func IsPalindrome(s sort.Interface) bool