version: extend token comparisons to strings, integers, and nil

[SeekingMeaning]

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This is useful for comparing version tokens, especially with #8183, for example:

Formula["gcc"].version.major > 6

[reitermarkus]

Suggested change

	version.scan(SCAN_PATTERN).map! { |token| Token.create(token) }
	version.scan(SCAN_PATTERN).map { |token| Token.create(token) }

[MikeMcQuaid]

Should this be returning nil or -1? It feels like this should maybe be part of the else case?

[Bo98]

nil represents that the two types are not comparable. In this case, if other isn't a valid token (and cannot be converted to one).

This line will also do a conversion from int/string to a token before hitting the case checks.

[MikeMcQuaid]

Works for me, thanks @Bo98!