// SetBase sets the position base.
	SetBase(*src.PosBase)
	// Line reports the source line number of the token.
	Line() int
	// Col reports the source column number of the token.
	Col() int
	// Close does any teardown required.
	Close()
}

// A Token is a scan token plus its string value.
// A macro is stored as a sequence of Tokens with spaces stripped.
type Token struct {
	ScanToken
	text string
}